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Circumcision and HIV
A lie will be halfway around the world before the truth has got its pants on.
- Rev. C. H. Spurgeon, 1855 who called it an old proverb
"Scientists have power by virtue of the respect commanded by the discipline. We may therefore be sorely tempted to misuse that power in furthering a personal prejudice or social goal -- why not provide that extra oomph by extending the umbrella of science over a personal preference in ethics or politics? But we cannot, lest we lose the very respect that tempted us in the first place."
- Stephen Jay Gould Bully for Brontosaurus, pp 429-30
(But some, it seems, are willing to take that risk.) |
It is not, of course, up to the media to decide what is good or bad science. The media was reporting what it heard from scientists [about cold fusion]. Only a tiny fraction of all scientific research is ever covered by the popular media, however, and most scientists go through their entire career without once encountering a reporter. New results and ideas are argued in the halls of research institutions, presented at scientific meetings, published in scholarly journals, all out of the public view. Voodoo science, by contrast, is usually pitched directly to the media, circumventing the normal process of scientific review and debate. ... The result is that a disproportionate share of the science seen by the public is flawed.
- "Voodoo Science" by Robert Park, pp26-7 |
Nail Soup
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Renal and Urology News August 19, 2009
"... circumcision must be combined with other techniques of HIV prevention, such as safe sex and voluntary testing. It is not sufficient to rely on circumcision alone to prevent HIV transmission."
- Ira Sharlip, MD, a specialist in sexual medicine at Pan Pacific Urology in San Francisco
A traveller came to a farmhouse and offered to make the occupants Nail Soup in return for a night's shelter. He threw a large nail in a pot of boiling water. But he said - "A nail must be combined with other soup ingredients, such as onions, carrots, meat and seasonings. It is not sufficient to rely on the nail alone to make Nail Soup."
In the morning he went on his way, refreshed after a night in a comfortable bed, minus the nail, with some gold coins in his pocket and the thanks of the family ringing in his ears for the wonderful nail that made such delicious Nail Soup.
So it will be when mass circumcision has been "rolled out" and if there is any dent at all in HIV transmission. |
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Checklist to determine the relationship between alleged cause and outcome
- What could be other possible causes of an observation?
- Can they be ruled out?
- If not, could they act in concert with the alleged cause,
or could they be part of a chain of events with the alleged
cause?
- Is there a plausible mechanism linking the alleged cause and
outcome?
- Do multiple studies link the alleged cause and outcome? Is
the relationship consistent across studies?
- Has the relationship held up across different individuals,
locations, and conditions, and over time? If not, is there a
logical reason that the relationship does not exist in all cases?
- Are the data being used to describe the relationship statistically significant, meaningful, free of confounding factors, and representative of reality rather than some quirk in the way the data were collected?
- Can the statistics be legitimately applied to the situation at hand?
Lies, Damned Lies and Science by Sherry Seethaler Pearson Education, NJ 2009, p110
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"Therefore Carthage must be destroyed"
(The Roman senator Cato was in the habit of ending every speech on any subject with those words - it helped that "must be destroyed" was a single splendid Latin word, "delenda". Eventually the Senate agreed to destroy Carthage, with disastrous consequences for Rome.) |
Recently, several studies have been published, most from Africa, one from India, claiming to show a link between having an intact penis and a higher risk of HIV infection. They tend to have two things in common - flawed work, and a passage near the end saying "Therefore, universal male circumcision should be considered as a preventive measure against HIV infection" or words to that effect.
This advice is folly.
- Any link between circumcision and HIV is statistically quite slight, so the protection would be quite inefficient compared to education in safe-sex practices and a culture of protected or otherwise safe(r) sex.
- The studies are trumpetted by their Relative Risk Reduction (RRR), currently running about 50-60%, but the corresponding Number Needed to Treat (NNT) is much less impressive. (In the latest Uganda study it is 56 circumcisions to prevent one HIV infection per year. That corresponds to 380 circumcisions/infection/year in the US, where AIDS is less prevalent.)
- As each new study corrects the errors of its predecessors, the protection claimed is less. When all the errors are corrected, what effect will be left?
In the case of randomised controlled trials (RCTs),
- While large numbers of men enter a trial, only a very small number are infected, making random errors high.
- The men were randomly assigned to be circumcised or left intact, but they were not a random sample of the population.
- They were all HIV-negative, meaning they were more likely to have any natural immunity than the rest of the population
- None were circumcised, meaning certain tribal groups had been selected out.
- All were willing to be circumcised
- They were significantly rewarded for taking part, skewing the socio-economic status of the sample
It may have been impossible to correct for these (since humans are not lab rats), but they are issues none the less.
- Significant numbers of men dropped out of the trials (were "lost to study"). Only those who stay the distance should be counted.
- Those who are circumcised and contract HIV will be more likely to drop out than the others because
- they got what they came for but
- circumcision didn't protect them, so they would be disillusioned with the trial.
- The three RCTs were cut short: this has reduced their accuracy.
- The control groups were then offered circumcision, making long-term follow-up impossible.
- Ethical approval for better studies will be harder to get, making these studies the last word.
- The gold standard of medical testing is the double blind random controlled trial. Circumcision can not be concealed from the experimenter or the subject. The control groups were not given a placebo operation.
- The after-effects of the operation are likely to alter sexual behaviour.
- In an experimental environment, the subjects got counselling and safe-sex advice that would not be available in a mass circumcision campaign.
- The circumcised group had specific instructions to abstain from sex and use condoms that the intact control group does not.
- Experimenter and circumcision advocate Robert Bailey has admitted that "repeated study visits and intensive behavioural counselling" of the circumcised men were needed to reduce risk behaviours.
If these results are acted on, with mass circumcision campaigns:
- Protection, if any, would be extended to a population, but it would be impossible to convince the average man that circumcision did not confer significant protection on him personally.
- The temptation would be irresistible - especially if he had submitted to a painful operation in adulthood - for a man to say "I'm circumcised, I'm safe".
- He would be more likely to lean on partners for unprotected sex
- This disempowers women
- Transmission from man to woman is easier than from woman to man. Circumcision has not been shown to protect women directly.
- Since circumcision desensitises the glans, men circumcised in adulthood would be less willing to use condoms than before.
- If they combine mass circumcision with Abstinence, Be faithful, Condoms, campaigns, as they propose, it will be impossible to tell what is responsible for the outcome: circumcision will be given the credit for any reduction, but will not have to take the blame for any lack of reduction.
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The latest study (2006) is the most careful so far to avoid the mistakes of its predecessors, but it still falls far short of justifying mass circumcision campagns of men in Africa, let alone Routine Infant Circumcision. It claims to have found a less protective effect than the one before it.
Flawed Studies
But each of these studies is flawed in one way or another.
- In the study of Kenyan truck drivers,
- 95 had intact penises, and of those, eleven men contracted HIV-1 in a 20 month period, compared to 32 of the 651 circumcised men in a 21 month period. That is to say, six more intact men contracted HIV-1 than the 5 out of 95 than the aggregated rate of 3.34 per hundred per year would predict. While this might look like a big difference, it is far too few, outside a laboratory, to draw any meaningful conclusions. "The law of small numbers" applies. Those six might have just been unlucky. Applying high-powered statistical methods to such a small sample as this, and with so many unknown variables, is using a sledgehammer to crack a nut.
- There were significant unexplained numerical discrepancies between two different publications of this study.
- The study's authors admit that circumcision is so closely tied to ethnicity that it was not possible to assess the effects of circumcision independently from those of ethnic origin.
- Nor were the effects assessed of ethnic origin or religion on other practices that might influence HIV-1 transmission, such as
- anal sex. An analysis of same-sex activity by the truck drivers, and how that is affected by ethnicity and religion, might cast a completely different light on the results. In the nature of things, membership of a tribe or ethnic group correlates with a variety of different customs, including sexual practices, and it may be those, rather than circumcision, that is responsible for any difference in HIV transmission.
- "dry sex": the use by women of herbal and other astringents to dry their vaginas (to increase men's pleasure, though it decreases their own). This causes micro-tears which can facilitatte HIV transmission.
- Female Genital Mutilation, which is practised only where male circumcision is also (with one exception, the Pokot of Kenya, and they used to circumcise males, but have given it up).
- A study released in Nairobi compares quite different populations of men. According to CBS: "The study focused on Benin's capital Cotonou and Cameroon's capital Yaounde, where circumcision is a widespread cultural practice, as well as the Zambian town of Ndola and the Kenyan town of Kisumu, where it is not." That is, the men compared lived in different countries, as much as 2300 miles (3600 km) apart!
- The Rakai study in Uganda showed no circumcised men contracting HIV during its 30 month course, and this fact has been made much of by the likes of Szabo and Short. They fail to mention that more than a third of the circumcised men were infected before the study started, and hence were not admitted to it. Thus all the men in the study had been selected in advance for less than average susceptibility to HIV.
However that selection could in turn be affected by circumcision status. Adolescent circumcision may delay the age of onset of intercourse (in societies where women won't have intercourse with intact men, unlike women in non-circumcising societies) which in turn would affect their chance of contracting HIV and being excluded from the study before it began. The lower HIV rate may have merely been a result of circumcised men having taken risks for longer than the intact men, and hence being more likely to have some immunity to HIV when they entered the study.
- A study published in Scientific American used nationality as a marker for circumcision status, yet African national boundaries are an historical accident arising frm the 19th Century "carve up of Africa".
- Other studies often rely on self-reporting of circumcision status. Where a man was circumcised in infancy, he may very well imagine he is intact because he looks like all his peers, and studies have shown a misapprehension of one's own status of as much as 33%.
- Only one of the African studies claims to have sufficiently corrected for the fact that circumcision in central Africa is largely a Muslim rite, and Islam requires
- ritual washing before prayer
- abstinence from alcohol
- periodic abstinence from sex, and
- marital fidelity
- all factors affecting HIV transmission. Islam allows polygamy, which makes extramarital sex less likely, just by exhaustion, and encourages female seclusion, which of course makes HIV transmission less likely.
That one study, confined to Christians in Kenya, compared men belonging to churches that encouraged circumcision with those that discouraged it. It used physical examination to determine circumcision status, and confined itself to churches that had similar views on polygamy and widow inheritance (of their late husbands' brothers as second husbands).
With those precautions, the correlation between circumcision status and HIV acquisition fell to 1.5 (20% of circumcised men had HIV, vs 30% of intact). With "adequate" genital hygiene, the rate among the intact fell to 26%. The circumcised men were more likely to be married and to have more than one wife, less likely to have ever been with a sex worker, or with more than three sex workers. (Equal proportions of both groups, 10-11%, had been with one or two sex workers.) These factors could well account for the difference.
The study had a 27% non-participation rate. The authors maintain that "because participants did not know their HIV-1 status at the time of our visit, bias from this source would seem unlikely." But many would know their HIV-1 status because of AIDS symptoms. All would know their circumcision status. There are thus unknown ways in which men might non-randomly "include themselves out".
This study - unlike others - found no effect of age of circumcision on HIV acquistion, even if the circumcision took place after sexual activity began and after HIV was prevalent. This suggests that circumcision itself is not the key factor. An unexplored area is what else the churches advocated or required beside circumcision. Since the church circumcisions occur on the eighth day after birth, it seems likely they model themselves on Judaism: what other Jewish practices do they advocate, and what effect could those have on HIV acquisition?
As controls on "psychic" research are tightened, the effects found steadily diminish, and when control is complete, the effects vanish. We see a similar effect here. These results are certainly consistent with the null hypothesis, that circumcision has no effect on HIV acquisition: the confounding factors have just not all been found yet. Yet as usual, this study advocates that "male circumcision should be seriously considered as an intervention to slow the spread of HIV-1 in uncircumcised populations". It is hard to escape the conclusion that this line was written before the study began.
- One study, of gay men who visited STD clinics in Seattle, relied on self-reporting, and also found a significant correlation between being circumcised and intra-venous drug use. This was not commented on (and the parallel conclusion, that circumcision should be discouraged in order to prevent IVDU, was of course not drawn). Again, only a small number of the men (thought they) were intact - 59 out of the 313 HIV+ men and 18 out of the 186 HIV- men.
- A study of men visiting STD clinics (which in itself skews the sample) in Pune, India is a classic example of inadvertent sorting by religion. In India, only Muslim (and Jewish) men are circumcised.
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From the lab bench to the glossies
...you have to be very cautious about how you extrapolate from what happens to some cells in a dish, on a laboratory bench, to the complex system of a living human being, where things can work in completely the opposite way what laboratory work would suggest. "Bad Science" by Ben Goldacre, Fourth Estate, London (2008), p 93
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- Two studies claim to find a mechanism for the proposed correlation, involving the Langerhans cells of the foreskin. However they base their conclusions on diametrically opposed data:
- A study much touted in early 2000, that of Szabo and Short, is based on a search of the literature (the other flawed studies just listed) plus a histological examination of the penises of 13 cadavers, all aged over 60, only 6 of them with foreskins. It found Langerhans cells on the inner mucosa and concluded that they facilitated HIV transmission.
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- That of arch-circumcisionist Gerald Weiss of seven years earlier examined the foreskins of a cohort of circumcised babies and found a deficiency of Langerhans cells, and concluded that their absence rendered the foreskin vulnerable to HIV transmission.
| These studies are contrasted side by side on another page.
- Another experimental study compares dead, excised foreskin tissue, with dead excised cervical tissue. It cites both the Short and Weiss studies without mentioning the contradiction between them. It cites the Quinn et al. (Rakai) study in Uganda that found 0 of 40 cut men seroconverting, compared to 40 out of 137 intact men - but ignores Quinn's reply to one of this paper's authors explaining why circumcision was not a factor.
It tests the uptake of HIV by foreskin tissue with that of uterine cervical tissue - rather than vaginal, labial or clitero-preputial mucosa, or the mucosa of the male glans for example - for no apparent reason. (One reason could be that cervical tissue was easier to obtain, via hysterectomy).
The dead foreskin and cervical tissue was subjected to an extraordinary amount of processing before it was even ready to be inoculated with HIV or HIV genes. The experimenters may answer that since the cervical and foreskin tissues were subjected to the same processing, any experimenter effects would be cancelled out - but, since they are different tissues, how does anyone know that?
They use skin from the outside of their sample foreskins as a surrogate for the shaft skin of circumcised men, but fail to take into account that only very low and tight circumcisions will result in a shaft covered only in skin: the traditional African method of drawing the foreskin forward on a block and slicing or chopping (as described by Nelson Mandela in excruciating detail in his autobiography) results in a circumcision that is low and loose, leaving plenty of mucosa.
Doubtless this study will now be cited again and again as proof that live
HIV is more likely to infect live intact men than live circumcised men -
even though no live penile tissue (and no circumcised penile tissue) was
involved in the experiments.
The paper again proposes mass circumcision as an HIV preventative measure, considering only "acceptablity and operational feasibility," not ethics. It throws a sop to the false sense of security this would engender, recommending
"...counselling parents and men against increasing sexual risk behaviours in the belief that circumcision fully protects against HIV acquisition."
In other words, they propose to persuade men to be circumcised because that will protect them, and simultaneously tell them not to have unsafe sex because it won't. A mixed message indeed!
A very limited target population, and far too few cases to tell
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National Prevention Information Network September 17, 2008
'Snip' Protects Some Gay Men from HIV: Study
Findings reported at the Australasian Sexual Health Conference
2008 shed new light on male circumcision’s role in preventing HIV
infection.
“We have shown for the first time that [men who have sex
with men] who predominantly take on the insertive role in sex are
less likely to contract HIV if they’ve been circumcised,” said Dr. David Templeton from the National Center for HIV Epidemiology
and Clinical Research in Sydney.
He went on to note, however,
“Most HIV infections are contracted in the receptive role, so what
we’re talking about is a risk reduction for a small group of men who
didn’t have a huge risk in the first place.” In the study, University of
New South Wales researchers recruited 1,400 HIV-negative men,
two-thirds of whom were circumcised. During the four-year study,
53 men acquired HIV. There was no evidence that circumcision
reduced the HIV risk among gay men in general. But in looking at
the men who predominantly took the insertive role in intercourse,
there was an 85 percent reduction in the risk of HIV infection if they
were circumcised. Only seven of the 53 HIV infections occurred
among insertive partners; the study’s model indicated that five of
these infections could have been avoided if the men had been
circumcised.
[No figure for how many of the seven HIV infections were among
circumcised insertive men. That's pathetically few to be drawing any
statistical conclusions from, and then only of correlation, not
causation. Were any of these men circumcised for religious
reasons? Factors like that might selectively influence their behaviour, putting them at less risk.]
Templeton was quick to note, however, “That’s only 9
percent of all HIV infections overall that can be attributed to being
uncircumcised, not enough to advocate throwing out condoms or
advocating widespread circumcision.”
Indeed, the study’s model
projected [by multiplying by thousands] that circumcising all Australian gay men would prevent
37 infections a year in the first decade and 57 per year by 2030, at
a cost of $196 million (US $153 million) in the first two years.
[No studies have been done of insertive-to-receptive transmission, cut vs
intact, but it seems likely the keratinised circumcised penis is more likely to tear the receptive anus or rectum, and there is much anecdotal evidence - and visual evidence from US vs European gay porn - that cut men are rougher,
because their fewer nerve-endings need more stimulation. So circumcising insertive men could readily increase HIV transmission to their partners. Yet already this study is being touted as a reason for gay men to get circumcised.]
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Misreported Studies
Studies that claim to find a correlation between intactness and HIV transmission are not uncommonly misreported in a way that plays up the "protective effect".
In one particularly glaring case, a study that found no statistical signficance was widely reported as finding a protective effect.
The study (Gray R et al. Male circumcision and the risks of female HIV and sexually transmitted infections acquisition in Rakai, Uganda. Thirteenth Conference on Retroviruses and Opportunistic Infections, Denver, abstract 128, 2006.) was an attempt to find whether circumcised men were less likely to infect their female partners with HIV.
299 couples where the man was intact were compared with 44 where the man was circumcised. After 30 months (if the pattern of the rest of the study was followed), infection rates were 7 per 100 person-years for the wives of circumcised men and 10 for the wives of intact men. This may look like a protective effect, but in statistical terms, p=0.22, meaning no statistical significance. In real terms, it can be back-calculated that 8 of the wives of circumcised men were infected. If 11 had been, the rate would be the same for both, and that difference of three infections in 30 months is too few to be considered significant.
But the study was widely reported (by Reuters) as showing that all 299 wives of intact men were infected, compared with only 44 wives of circumcised men, as if these were just the small (infected) samples of two much larger and equal samples. This makes the supposed protective effect look much greater.
See the garbled report and the relevant part of a more accurate report.
Why, one wonders, was the study ever published, and why in this very
misleading form?
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If at first you don't find significance...
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Torture the data
If your results are bad, ask the computer to go back and see if any particular subgroups behaved differently. You might find that your drug works very well in Chinese women aged fifty-two to sixty-one. 'Torture the data and it will confess to anything,' as they say at Guantanamo Bay.
"Bad Science" by Ben Goldacre, Fourth Estate, London (2008), p 210
This is commonly called "data-mining" This cartoon illustrates the principle.
In the following study, the vast majority of the men showed no correlation between intactness and HIV. "Known risk" was defined by the experimenters and left only 50 intact men.
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The Journal of Infectious Diseases (impact factor: 5.87). 01/2009; 199(1):59-65. DOI: 10.1086/595569
Male Circumcision and Risk of HIV Infection
among Heterosexual African American Men
Attending Baltimore Sexually Transmitted Disease
Clinics
Lee Warner, Khalil G. Ghanem, Daniel R. Newman, Maurizio Macaluso, Patrick S. Sullivan, and
Emily J. Erbelding
Background. Male circumcision has received international attention as an intervention for reducing HIV infection among high-risk heterosexualmen; however, few US studies have evaluated its association with the risk of HIV infection.
Methods. We analyzed visit records for heterosexual African American men who underwent HIV testing while attending sexually transmitted disease (STD) clinics in Baltimore, Maryland, from 1993 to 2000. We used multivariable binomial regression to evaluate associations between circumcision and the risk of HIV infection among visits by patients with known and unknown HIV exposure.
Results. Overall, 1096 (2.7%) of 40,571 clinic visits yielded positive HIV test results. Among 394 visits by [385] patients [fewer than 50 of whom were intact] with known HIV exposure, circumcision was significantly associated with lower HIV prevalence (10.2% vs. 22.0% [i.e. about 11 intact men compared to about 5 who might not have contracted HIV if they had been circumcised]; adjusted prevalence rate ratio [PRR], 0.49 [95% confidence interval [CI], 0.26–0.93]). [The question arises, how can you "adjust" {for age, STDs, year of visit, and clinic location} when you are dealing with only 385 men, and only 50 of them intact.] Conversely, among 40,177 visits by patients with unknown HIV exposure, circumcision was not associated with reduced HIV prevalence (2.5% vs. 3.3%; adjusted PRR, 1.00 [95% CI, 0.86 –1.15]), and age =>25 years old and diagnosis of ulcerative STD were associated with increased prevalence.
Conclusions. Circumcision was associated with substantially reduced HIV risk in patients with known HIV exposure, suggesting that results of other studies demonstrating reduced HIV risk for circumcision among heterosexual men likely can be generalized to the US context. [The suggestion does not follow from the evidence.]
[This study has generated a flurry of headlines like "Circumcision significantly cuts HIV infection risk in heterosexual men" but the key phrase "with known HIV exposure" was usually omitted.
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Contrary Studies
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A failed prediction is a very solid sign that a pattern is phony. A pattern allows you to make a prediction: ... A false pattern has no predictive power: it might seem to give you a lot of power to understand past data, but it completely breaks down when tested against new data.
- Charles Seife, Proofiness, p56f
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No protection to men in Kenya
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Elites TV December 18, 2010
Using a population-based survey we examined the behaviors, beliefs, and HIV/HSV-2 serostatus of men and women in the traditionally non-circumcising community of Kisumu, Kenya prior to establishment of voluntary medical male circumcision services. A total of 749 men and 906 women participated. Circumcision status was not associated with HIV/HSV-2 infection
nor increased high risk sexual behaviors. In males, preference for being or becoming circumcised was associated with inconsistent condom use and increased lifetime number of sexual partners. Preference for circumcision was increased with understanding [i.e. indoctrination] that circumcised men are less likely to become infected with HIV.
[The study, by Robert Bailey et al. writes off the lack of association to "possible ... limitations in sample size and prevalence." 108 men with sexual experience out of 749 tested HIV+. The circumcision rate was 25% by self-report and 28% by examination. Raw figures for circumcision vs HIV are not given.]
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Circumcsion does not protect black South Africans
A total of 2585 males over the age of 15 were administered
questionnaires and provided specimens for HIV testing.
916 (35.4%) of them said they were circumcised. HIV
prevalence among circumcised males was 10.7% and among uncircumcised males
was 12.1%, p = 0.9 [i.e. no statistical significance]. Blacks were less likely to be circumcised (28.8%)
compared to other racial groups, 42.6%, p = 0.002. When the data was
stratified by racial group, circumcised Blacks showed similar rates of HIV
as uncircumcised Blacks, (OR: 0.8, p = 0.4) however other racial groups
showed a strong protective effect, (OR: 0.3, p = 0.01) [or rather, a correlation]. When the
data are further stratified by age of circumcision, there is a slight
protective effect [correlation] between early circumcision and HIV among Blacks, OR:
0.7, p = 0.4.
Conclusion In general, circumcision offers slight
protection. The effect is much stronger in other racial groups than in
blacks. This racial difference cannot be explained by age of circumcision.
HIV and circumcision in South Africa
C.A. Connolly, O. Shisana, L. Simbayi, M. Colvin.
Poster at the XV AIDS Conference in Bangkok [MoPeC3491] |
Those "protective effects" disappeared on further analysis
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South African Medical Journal, October 2008, Vol. 98, No. 10
Male circumcision and its relationship to HIV infection in
South Africa: Results of a national survey in 2002
Catherine Connolly, Leickness C Simbayi, Rebecca Shanmugam, Ayanda Nqeketo
Objective. To investigate the nature of male circumcision and
its relationship to HIV infection.
Methods. Analysis of a sub-sample of 3 025 men aged 15 years
and older who participated in the first national population-based
survey on HIV/AIDS in 2002. Chi-square tests and
Wilcoxon rank sum tests were used to identify factors
associated with circumcision and HIV status, followed by a
logistic regression model.
Results. One-third of the men (35.3%) were circumcised. The
factors strongly associated with circumcision were age >50,
black living in rural areas and speaking SePedi (71.2%) or
IsiXhosa (64.3%). The median age was significantly older
for blacks (18 years) compared with other racial groups (3.5
years), p <0.001. Among blacks, circumcisions were mainly
conducted outside hospital settings. In 40.5% of subjects,
circumcision took place after sexual debut; two-thirds of
the men circumcised after their 17th birthday were already
sexually active. HIV and circumcision were not associated
(12.3% HIV positive in the circumcised group v. 12% HIV
positive in the uncircumcised group). HIV was, however,
significantly lower in men circumcised before 12 years of
age (6.8%) than in those circumcised after 12 years of age
(13.5%, p=0.02). When restricted to sexually active men, the
difference that remained did not reach statistical significance
(8.9% v. 13.6%, p=0.08.). There was no effect when adjusted for
possible confounding.
Conclusion. Circumcision had no protective effect in the
prevention of HIV transmission. This is a concern, and has
implications for the possible adoption of the mass male
circumcision strategy both as a public health policy and an
HIV prevention strategy.
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No protection among young South Africans
A 2001 study by Bertran Auvert et al (who also ran the 2005 Random Controlled Study) of HIV infection among youth in a South African mining town found it is associated with the Herpes simplex 2 virus
It was "a community-based, cross-sectional study" of a random sample of men (n = 723) and women (n = 784) living in a township in the Carletonville district of South Africa.
Risk factors associated with HIV were recorded by questionnaire and biological tests were performed on serum and urine. It found that women were much more likely to have HIV (34%) than men (9%) and HSV-2 (53% vs 17%) Two thirds of the 24-year-old women had HIV. Of the men,
Circumcision status | n
| HIV+
| Odds ratio | 95% Confidence interval |
No | 498 (89.1%) | 11.2% | 1 | |
Yes | 61 (10.9%) | 16.4% | 1.6 | 0.7-3.2 |
Thus, the circumcised men in the study were more likely to be HIV+, but the difference was not statistically significant (the 95% CI straddles 1.0 - in real terms, 10 of the 61 circumcised men had HIV, three more than would be expected if they had the same rate as the intact men) But it certainly casts doubts on the claim that circumcision protects against HIV infection. Typically, Auvert expresses this cautiously, in terms of the prevailing mythology - which he has done so much to promote: "No protective effect of circumcision on HIV prevalence was shown."
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No protection to gay men
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Gust DA, Wiegand RE, Kretsinger K, Sansom S, Kilmarx PH, Bartholow BN, Chen RT.
OBJECTIVE: Determine whether male circumcision would be effective in reducing HIV transmission among men who have sex with men (MSM).
DESIGN: Retrospective analysis of the VAXGen VAX004 HIV vaccine clinical trial data. [Since the men were all volunteers in a vaccine trial, they were not a random sample of the population.]
METHODS: Survival analysis was used to associate time to HIV infection with multiple predictors. Unprotected insertive and receptive anal sex predictors were highly correlated, thus separate models were run.
RESULTS: Four thousand eight hundred and eighty-nine participants were included in this reanalysis; 86.1% were circumcised. Three hundred and forty-two (7.0%) men became infected during the study; 87.4% [4209] were circumcised. [So 680 were intact, of whom only 43 became HIV+, according to this news item, or 6.3%. And the rate among the circumcised men is (342-43)/4209 or 7.1% ] Controlling for demographic characteristics and risk behaviors, in the model that included unprotected insertive anal sex, being uncircumcised was not associated with incident HIV infection [adjusted hazards ratio (AHR) = 0.97, confidence interval (CI) = 0.56-1.68]. Furthermore, while having unprotected insertive (AHR = 2.25, CI = 1.72-2.93) or receptive (AHR = 3.45, CI = 2.58-4.61) anal sex with an HIV-positive partner were associated with HIV infection, the associations between HIV incidence and the interaction between being uncircumcised and reporting unprotected insertive (AHR = 1.78, CI = 0.90-3.53) or receptive (AHR = 1.26, CI = 0.62-2.57) anal sex with an HIV-positive partner were not statistically significant. Of the study visits when a participant reported unprotected insertive anal sex with an HIV-positive partner, HIV infection among circumcised men was reported in 3.16% of the visits (80/2532) and among uncircumcised men in 3.93% of the visits (14/356) [relative risk (RR) = 0.80, CI = 0.46-1.39]. [This is data-mining. The number who knew the HIV+ status of their partners would be a small and random fraction of the total, as the wide Confidence Intervals indicate.]
CONCLUSIONS: Among men who reported unprotected insertive anal sex with HIV-positive partners, being uncircumcised did not confer a statistically significant increase in HIV infection risk [The possiblity that circumcision increases the risk is not considered, even though the figures "trend" that way.]. Additional studies with more incident HIV infections or that include a larger proportion of uncircumcised men may provide a more definitive result.
PMID: 20168206 [PubMed - as supplied by publisher] |
No protection to insertive gay men:
"Our finding that 17% of homosexual men with newly acquired HIV infection reported insertive UAI [unprotected anal intercourse] as their highest risk activity suggests that insertive UAI is an important means of HIV transmission in this population. However, we found no association between circumcision status and infection by insertive UAI. In addition, men who had seroconverted despite no reported event of UAI were also no more likely to be uncircumcised. These data strongly suggest that the foreskin is not the main source of HIV infection in homosexual men who become infected by insertive UAI, and that other sites, such as the distal urethra, must be important in HIV infection.
"Our data showing that there is no difference in the circumcision status of men infected by receptive or insertive UAI, in a population with a circumcision prevalence of approximately 75%, suggests that circumcision is not strongly protective against HIV infection in homosexual men. Larger studies, preferably of prospective design, are needed to confirm the absence of a relationship between circumcision and HIV infection risk in gay men. In the meantime, educational messages to homosexual men should continue to emphasize that insertive anal sex is a high-risk activity for HIV transmission whether or not the insertive partner is circumcised."
- Grulich AE, Hendry O, Clark E, Kippax S, Kaldor JM.
Circumcision and male-to-male sexual transmission of HIV.
AIDS 2001 Jun 15;15(9):1188-1189.
A longer-term study of the same men did find significantly less HIV in strictly insertive men ("tops") who were circumcised, but it is based on
- a grand total of three intact men who might not have got HIV if they had been circumcised. By Fisher's exact test, the two-tailed P-value = 0.1035 and the association is not significant.
"As the minority of HIV infections in H[ealth] I[n ]M[en -a prospective cohort study of homosexual men in Sydney] occurred in those reporting no receptive U[unprotected ]A[mal ]Intercourse ], and most Australian men are circumcised, circumcision is unlikely to have a major impact on HIV incidence in homosexual men in Australia. Nonetheless, 'strategic positioning' when HIV-negative gay men adopt the insertive role in UAI to reduce their HIV risk is occurring commonly among Sydney gay men. This coupled with a rapidly declining prevalence of circumcision in Australian and US homosexual men means circumcision could play a more important role in reducing gay men's susceptibility to HIV infection in the future. Randomized trials are warranted before recommendations can be made regarding circumcision as an HIV prevention intervention among MSM populations, but the design of such studies is challenging. [A Tuskegee-style study would be required] Study populations would require high HIV incidence, low baseline circumcision prevalence and large numbers of participants exclusively or predominantly practising the insertive role. Such attributes are necessary for sufficient study power to detect an association of circumcision status with the relatively infrequent outcome measure of HIV acquisition via insertive anal intercourse."
- Templeton DJ, Jin F, Mao L, Prestage GP, Donovan B, Imrie J, Kippax S, Kaldor JMa, Grulich AE Circumcision and risk of HIV infection in Australian homosexual men AIDS 2009 Nov 13:23(17): 2347-2351.
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Arch Sex Behav. 2013 Jan 29. [Epub ahead of print]
Circumcision and HIV Infection among Men Who Have Sex with Men in Britain: The Insertive Sexual Role.
Doerner R, McKeown E, Nelson S, Anderson J, Low N, Elford J.
Abstract
The objective was to examine the association between circumcision status and self-reported HIV infection among men who have sex with men (MSM) in Britain who predominantly or exclusively engaged in insertive anal intercourse. In 2007-2008, a convenience sample of MSM living in Britain was recruited through websites, in sexual health clinics, bars, clubs, and other venues. Men completed an online survey which included questions on circumcision status, HIV testing, HIV status, sexual risk behavior, and sexual role for anal sex. The analysis was restricted to 1,521 white British MSM who reported unprotected anal intercourse in the previous 3 months and who said they only or mostly took the insertive role during anal sex. Of these men, 254 (16.7 %) were circumcised. Among men who had had a previous HIV test (n = 1,097), self-reported HIV seropositivity was 8.6 % for circumcised men (17/197) and 8.9 % for uncircumcised men (80/900) (unadjusted odds ratio [OR], 0.97; 95 % confidence interval [95 % CI], 0.56, 1.67). In a multivariable logistic model adjusted for known risk factors for HIV infection, there was no evidence of an association between HIV seropositivity and circumcision status (adjusted OR, 0.79; 95 % CI, 0.43, 1.44), even among the 400 MSM who engaged exclusively in insertive anal sex (adjusted OR, 0.84; 95 % CI, 0.25, 2.81). Our study provides further evidence that circumcision is unlikely to be an effective strategy for HIV prevention among MSM in Britain.
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No protection to Seattle men who have sex with men - even the exclusively insertive
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Sex Transm Dis. 2009 Nov 6. [Epub ahead of print]
The [Lack of] Association Between Lack of Circumcision and HIV, HSV-2, and
Other Sexually Transmitted Infections Among Men Who Have Sex With Men.
Jameson DR, Celum CL, Manhart L, Menza TW, Golden MR.
BACKGROUND:: Observational studies evaluating the association of
circumcision and HIV infection among men who have sex with men (MSM)
have yielded mixed results. We examined the relationship between
circumcision and HIV, herpes simplex virus type-2 (HSV-2), syphilis,
urethral gonorrhea, and urethral chlamydia among MSM stratified by
anal sexual role.
METHODS:: Between October 2001 and May 2006, 4749
MSM who reported anal intercourse in the previous 12 months attended
the Public Health-Seattle and King County STD clinic for 8337
evaluations. Clinicians determined circumcision status by examination
and anal sexual role in the previous year by interview. Blood samples
were used to test HIV, syphilis, and HSV-2 serostatus. Urethral
gonorrhea and chlamydia were tested by culture or nucleic acid
amplification. We used generalized estimating equations to evaluate
the association between circumcision and specific diagnoses, adjusted
for race/ethnicity and age.
RESULTS:: Among the 3828 men whose
circumcision status was assessed, 3241 (85%) were circumcised and 587
(15%) were not. The proportion of men newly testing HIV-positive or
with previously diagnosed HIV did not differ by circumcision status
when stratified by men's anal sexual role in the preceding year, even
when limited to men who reported only insertive anal intercourse in
the preceding 12 months (OR = 1.45; 95% CI: 0.30, 7.12). Similarly,
we did not observe a significant association between circumcision
status and the other sexually transmitted infections (STI).
CONCLUSIONS:: Our findings suggest that male circumcision would not
be likely to have a significant impact on HIV or sexually transmitted
infections acquisition among MSM in Seattle.
PMID: 19901865 [PubMed - as supplied by publisher]
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No protection to US men who have sex with men
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AIDS Patient Care and STDs
Relations Between Circumcision Status, Sexually Transmitted Infection History, and HIV Serostatus Among a National Sample of Men Who Have Sex with Men in the United States
Kristen Jozkowski, Joshua G. Rosenberger, Vanessa Schick, Debby Herbenick, David S. Novak, Michael Reece. AIDS Patient Care and STDs. August 2010, 24(8): 465-470.
Abstract
Circumcision's potential link to HIV/sexually transmitted infections (STI) has been at the center of recent global public health debates. However, data related to circumcision and sexual health remain limited, with most research focused on heterosexual men. This study sought to assess behavioral differences among a large sample of circumcised and noncircumcised men who have sex with men (MSM) in the United States. Data were collected from 26,257U.S. MSM through an online survey. [An online survey is a population sample of unknown randomness.] Measures included circumcision status, health indicators, HIV/STI screening and diagnosis, sexual behaviors, and condom use. Bivariate and regression analyses were conducted to determine differences between HIV/STI status, sexual behaviors, and condom use among circumcised and noncircumcised men. Circumcision status did not significantly predict HIV testing (p>0.05), or HIV serostatus (p>0.05), and [there were no significant differences based on circumcision status for most STI diagnosis [syphilis, gonorrhea, chlamydia, human papilloma virus (HPV)]. Being noncircumcised was predictive of herpes-2 diagnosis, however, condom use mediated this relationship.] [That is, circumcised men were more likely to use condoms, and it was this that protected them from herpes, not being circumcised. This suggests that being circumcised increased their risk of the other STIs.] These data provide one of the first large national assessments of circumcision among MSM. While being noncircumcised did not increase the likelihood of HIV and most STI infections, results indicated that circumcision was associated with higher rates of condom use, suggesting that those who promote condoms among MSM may need to better understand condom-related behaviors and attitudes among noncircumcised men to enhance the extent to which they are willing to use condoms consistently.
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No protection to US Black and Latino men who have unprotected insertive sex with men
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JAIDS December 15, 2007
Circumcision Status and HIV Infection Among Black and Latino Men Who Have Sex With Men in 3 US Cities.
Millett, Gregorio A; Ding, Helen; Lauby, Jennifer; Flores, Stephen; Stueve, Ann; Bingham, Trista; Carballo-Dieguez, Alex; Murrill, Chris; Liu, Kai-Lih; Wheeler, Darrell; Liau, Adrian; Marks, Gary
Abstract:
Objective: To examine characteristics of circumcised and uncircumcised Latino and black men who have sex with men (MSM) in the United States and assess the association between circumcision and HIV infection.
Methods: Using respondent-driven sampling, 1154 black MSM and 1091 Latino MSM were recruited from New York City, Philadelphia, and Los Angeles. A 45-minute computer-assisted interview and a rapid oral fluid HIV antibody test (OraSure Technologies, Bethlehem, PA) were administered to participants.
Results: Circumcision prevalence was higher among black MSM than among Latino MSM (74% vs. 33%; P < 0.0001). Circumcised MSM in both racial/ethnic groups were more likely than uncircumcised MSM to be born in the United States or to have a US-born parent. Circumcision status was not associated with prevalent HIV infection among Latino MSM, black MSM, black bisexual men, or black or Latino men who reported being HIV-negative based on their last HIV test. Further, circumcision was not associated with a reduced likelihood of HIV infection among men who had engaged in unprotected insertive and not unprotected receptive anal sex.
Conclusions: In these cross-sectional data, there was no evidence that being circumcised was protective against HIV infection among black MSM or Latino MSM.
JAIDS Journal of Acquired Immune Deficiency Syndromes. 46(5):643-650, December 15, 2007.
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No protection to Scottish men who have sex with men
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Sex Transm Infect. 2010 Jun 30
Circumcision among men who have sex with men in Scotland: limited potential for HIV
prevention.
McDaid LM, Weiss HA, Hart GJ.
Abstract
Objective Male circumcision has been shown to reduce the risk of HIV
acquisition among heterosexual men but the impact among men who have
sex with men (MSM) is not known. In this paper, we explore the
feasibility of research into circumcision for HIV prevention among
MSM in Scotland.
Methods Anonymous, self-complete questionnaires and
Orasure oral fluid collection kits were distributed to men visiting
the commercial gay scenes in Glasgow and Edinburgh.
Results 1508 men completed questionnaires (70.5% response rate) and 1277 provided oral
fluid samples (59.7% response rate). Overall, 1405 men were eligible
for inclusion in the analyses. 16.6% reported having been
circumcised. HIV prevalence was similar among circumcised and
uncircumcised men (4.2% and 4.6%, respectively). Although
biologically, circumcision is most likely to protect against HIV for
men practising unprotected insertive anal intercourse (UIAI), only
7.8% (91/1172) of uncircumcised men reported exclusive UIAI in the
past 12 months. Relatively few men reported being willing to
participate in a research study on circumcision and HIV prevention
(13.9%), and only 11.3% of uncircumcised men did so.
Conclusion The lack of association between circumcision and HIV status, low levels of exclusive UIAI, and low levels of willingness to take part in
circumcision research studies suggest circumcision is unlikely to be
a feasible HIV prevention strategy for MSM in the UK. Behaviour
change should continue to be the focus of HIV prevention in this
population.
PMID: 20595141
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No protection to women
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The Lancet, Volume 374, Issue 9685, Pages 229 - 237, 18 July 2009
Circumcision in HIV-infected men and its effect on HIV transmission to female partners in Rakai, Uganda: a randomised controlled trial
Dr, Prof Maria J Wawer MD, Frederick Makumbi PhD, Godfrey Kigozi MBChB, David Serwadda MMed, Stephen Watya MMed, Fred Nalugoda MHS, Dennis Buwembo MBChB, Victor Ssempijja ScM, Noah Kiwanuka MBChB, Prof Lawrence H Moulton PhD, Nelson K Sewankambo MMed, Steven J Reynolds MD, Thomas C Quinn MD, Pius Opendi MBChB, Boaz Iga MSc, Renee Ridzon MD, Oliver Laeyendecker MBA, Prof Ronald H Gray MD
Summary
Background
Observational studies have reported an association between male circumcision and reduced risk of HIV infection in female partners. We assessed whether circumcision in HIV-infected men would reduce transmission of the virus to female sexual partners.
Methods
922 uncircumcised, HIV-infected, asymptomatic men aged 15-49 years with CD4-cell counts 350 cells per ?L or more were enrolled in this unblinded, randomised controlled trial in Rakai District, Uganda. Men were randomly assigned by computer-generated randomisation sequence to receive immediate circumcision (intervention; n=474) or circumcision delayed for 24 months (control; n=448). HIV-uninfected female partners of the randomised men were concurrently enrolled (intervention, n=93; control, n=70) and followed up at 6, 12, and 24 months, to assess HIV acquisition by male treatment assignment (primary outcome). A modified intention-to-treat (ITT) analysis, which included all concurrently enrolled couples in which the female partner had at least one follow-up visit over 24 months, assessed female HIV acquisition by use of survival analysis and Cox proportional hazards modelling. This trial is registered with ClinicalTrials.gov, number NCT00124878.
Findings
The trial was stopped early because of futility. [That is, it failed to find any protection. It might have shown increased risk, but they weren't interested in that.] 92 couples in the intervention group and 67 couples in the control group were included in the modified ITT analysis. 17 (18%) women in the intervention group and eight (12%) women in the control group acquired HIV during follow-up (p=0·36). Cumulative probabilities of female HIV infection at 24 months were 21·7% (95% CI 12·7-33·4) in the intervention group and 13·4% (6·7-25·8) in the control group (adjusted hazard ratio 1·49, 95% CI 0·62-3·57; p=0·368).
Interpretation
Circumcision of HIV-infected men did not reduce HIV transmission to female partners over 24 months; longer-term effects could not be assessed. Condom use after male circumcision is essential for HIV prevention.
Funding
Bill & Melinda Gates Foundation with additional laboratory and training support from the National Institutes of Health and the Fogarty International Center.
A YouTube video of Maria Wawer describing the experiment
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Author: Turner AN | Morrison CS | Padian NS | Kaufman JS | Salata RA
Source: AIDS. 2007 Aug 20;21(13):1779-1789.
Abstract: The objective was to assess whether male circumcision of the primary sex partner is associated with women's risk of HIV. Data were analyzed from 4417 Ugandan and Zimbabwean women participating in a prospective study of hormonal contraception and HIV acquisition. Most were recruited from family planning clinics; some in Uganda were referred from higher-risk settings such as sexually transmitted disease clinics. Using Cox proportional hazards models, time to HIV acquisition was compared for women with circumcised or uncircumcised primary partners. Possible misclassification of male circumcision was assessed using sensitivity analysis. At baseline, 74% reported uncircumcised primary partners, 22% had circumcised partners and 4% had partners of unknown circumcision status. Median follow-up was 23 months, during which 210 women acquired HIV (167, 34, and 9 women whose primary partners were uncircumcised, circumcised, or of unknown circumcision status, respectively). Although unadjusted analyses indicated that women with circumcised partners had lower HIV risk than those with uncircumcised partners, the protective effect disappeared after adjustment for other risk factors [hazard ratio (HR), 1.03; 95% confidence interval (CI), 0.69-1.53]. Subgroup analyses suggested a non-significant protective effect of male circumcision on HIV acquisition among Ugandan women referred from higher-risk settings: adjusted HR 0.16 (95% CI, 0.02-1.25) but little effect in Ugandans (HR, 1.33; 95% CI, 0.72-2.47) or Zimbabweans (HR, 1.12; 95% CI, 0.65-1.91) from family planning clinics. After adjustment, male circumcision was not significantly associated with women's HIV risk. The potential protection offered by male circumcision for women recruited from high-risk settings warrants further investigation. (author's)
Date Posted: 3 September 2007
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AIDS. 2009 Dec 29. [Epub ahead of print]
Male circumcision and risk of male-to-female HIV-1 transmission: a
multinational prospective study in African HIV-1-serodiscordant
couples.
Baeten JM, Donnell D, Kapiga SH, Ronald A, John-Stewart G, Inambao M,
Manongi R, Vwalika B, Celum C; for the Partners in Prevention HSV/HIV
Transmission Study Team.
OBJECTIVE:: Male circumcision reduces female-to-male HIV-1
transmission risk by approximately 60%. Data assessing the effect of
circumcision on male-to-female HIV-1 transmission are conflicting, with
one observational study among HIV-1-serodiscordant couples showing reduced
transmission but a randomized trial suggesting no short-term benefit of
circumcision.
[Suggesting an increased risk, actually]
DESIGN/METHODS:: Data collected as part of a prospective
study among African HIV-1-serodiscordant couples were analyzed for the
relationship between circumcision status of HIV-1-seropositive men and
risk of HIV-1 acquisition among their female partners. Circumcision status
was determined by physical examination. Cox proportional hazards analysis
was used.
RESULTS:: A total of 1096 HIV-1-serodiscordant couples in which
the male partner was HIV-1-infected were followed for a median of 18
months; 374 (34%) male partners were circumcised. Sixty-four female
partners seroconverted to HIV-1 (incidence 3.8 per 100 person-years). [It would be useful to know the raw figures, circumcised vs intact partners, at this point.]
Circumcision of the male partner was associated with a nonstatistically
significant approximately 40% lower risk of HIV-1 acquisition by the
female partner (hazard ratio 0.62, 95% confidence interval 0.35-1.10, P = 0.10). [Translation: no protection.]
The magnitude of this effect was similar when restricted to the
subset of HIV-1 transmission events confirmed by viral sequencing to have
occurred within the partnership (n = 50, hazard ratio 0.57, P = 0.11),
after adjustment for male partner plasma HIV-1 concentrations (hazard
ratio 0.60, P = 0.13), and when excluding follow-up time for male partners
who initiated antiretroviral therapy (hazard ratio 0.53, P = 0.07). [Translation: data-mining failed to find an effect.]
CONCLUSION:: Among HIV-1-serodiscordant couples in which the
HIV-1-seropositive partner was male, we observed no increased risk and
potentially decreased risk from circumcision on male-to-female
transmission of HIV-1.
[An attempt to snatch victory from the jaws of defeat. The risk was not decreased.]
PMID: 20042848 [PubMed - as supplied by publisher] |
Greater risk to women whose partners are circumcised:
Int J Epidemiol. 1994 Apr;23(2):371-80.
Risk factors associated with prevalent HIV-1 infection among pregnant women in Rwanda. National University of Rwanda-Johns Hopkins University AIDS Research Team.
Chao A, Bulterys M, Musanganire F, Habimana P, Nawrocki P, Taylor E, Dushimimana A, Saah A.
Department of Epidemiology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, MD 21205.
Abstract: This study evaluated risk factors associated with prevalent HIV-1 infection among pregnant women in a semi-rural but densely populated area surrounding the town of Butare in Rwanda. Overall seroprevalence was 9.3% in 5690 pregnant women who sought antenatal care at one of five health centres. Factors associated with higher seroprevalence of HIV-1 included history of multiple sexual partners, history of at least one sexually transmitted disease (STD), relatively high socioeconomic status (SES), being unmarried, young age at first pregnancy, and low gravidity. Women who had used oral contraceptives, smoked more than one cigarette per day, whose partners were circumcised, and had had sex to support themselves were also at higher risk of being infected. A history of blood transfusion in the past 5 years was not associated with HIV-1 infection. History of multiple sexual partners, history of STD, high household income, partner circumcision, and past oral contraceptive use remained strongly associated with HIV-1 infection even when simultaneously controlling for other covariates. Among legally married women who lacked sexual behaviour risk factors, history of STD, high SES, young age at first pregnancy, and low gravidity were significantly associated with HIV-1 seroprevalence.
PMID: 8082965 [PubMed - indexed for MEDLINE] |
No correlation in a high-risk population
International AIDS Society
Prevalence of male circumcision and its association with HIV and sexually transmitted infections in a U.S. navy population
A G Thomas, L N Bakhireva, S K Brodine, R A Shaffer
Int Conf AIDS. 2004 Jul 11-16; 15: abstract no. TuPeC4861.
Background: Lack of male circumcision has been found to be a risk factor for HIV and sexually transmitted infection (STI) in several studies performed in developing countries. However, the few studies conducted in developed nations have yielded inconsistent results. Policy regarding circumcision of male infants as a prevention measure against HIV/STI remains a controversial topic. This study describes the prevalence of circumcision and its association with HIV and STI in a U.S. military population.
Methods: This is a case-control study of male HIV infected U.S. military personnel (n= 232) recruited from 7 military medical centers and male U.S. Navy controls (n=516) from a general aircraft carrier population. Cases and controls completed similar self-administered HIV behavioral risk surveys. Case circumcision status was abstracted from medical charts while control status was reported on the survey. Cases and controls were frequency matched on age. Multiple logistic regressions were constructed separately to evaluate the role of circumcision in the acquisition of HIV and STI.
Results: The proportion of circumcised men did not significantly differ between cases (84.9%) and controls (81.8%). Prevalence of circumcision among men born in the U.S. was higher (85.0%) than those born elsewhere (58.1%). After adjustment for demographic and behavioral risk factors lack of circumcision was not found to be a risk factor for HIV (OR = 0.9; 95% CI: 0.51, 1.7) or STI (OR = 1.08; 95% CI 0.52, 2.26). The odds of HIV infection were 2.6 higher for irregular condom users, 5 times as high for those reporting STI, 6.2 times higher for those reporting anal sex, 2.8-3.2 times higher for those with 2-7+ partners, nearly 3 times higher for Blacks, and 3.5 times as high for men who were single or divorced/separated.
Conclusions: Although there may be other medical or cultural reasons for male circumcision, it is not associated with HIV or STI prevention in this U.S. military population.
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No protection by traditional circumcision
J Acquir Immune Defic Syndr. 2007 Aug 1;45(4):371-9.
The protective effect of circumcision on HIV incidence in rural low-risk men circumcised predominantly by traditional circumcisers in Kenya: two-year follow-up of the Kericho HIV Cohort Study.
Shaffer DN, Bautista CT, Sateren WB, Sawe FK, Kiplangat SC, Miruka AO, Renzullo PO, Scott PT, Robb ML, Michael NL, Birx DL.
US Army Medical Research Unit, Walter Reed Project HIV Program, Kericho, Kenya. dshaffer@wrp-kch.org
BACKGROUND: Three randomized controlled trials (RCTs) have demonstrated that male circumcision prevents female-to-male HIV transmission in sub-Saharan Africa. Data from prospective cohort studies are helpful in considering generalizability of RCT results to populations with unique epidemiologic/cultural characteristics. METHODS: Prospective observational cohort sub-analysis. A total of 1378 men were evaluated after 2 years of follow-up. Baseline sociodemographic and behavioral/HIV risk characteristics were compared between 270 uncircumcised and 1108 circumcised men. HIV incidence rates (per 100 person-years) were calculated, and Cox proportional hazards regression analyses estimated hazard rate ratios (HRs). RESULTS: Of the men included in this study, 80.4% were circumcised; 73.9% were circumcised by traditional circumcisers. Circumcision was associated with tribal affiliation, high school education, fewer marriages, and smaller age difference between spouses (P < 0.05). After 2 years of follow-up, there were 30 HIV incident cases (17 in circumcised and 13 in uncircumcised men). Two-year HIV incidence rates were 0.79 (95% confidence interval [CI]: 0.46 to 1.25) for circumcised men and 2.48 (95% CI: 1.33 to 4.21) for uncircumcised men corresponding to a HR = 0.31 (95% CI: 0.15 to 0.64). In one model controlling for sociodemographic factors, the HR increased and became non-significant (HR = 0.55; 95% CI: 0.20 to 1.49). CONCLUSIONS: Circumcision by traditional circumcisers offers protection [That's not what "non-significant" means.] from HIV infection in adult men in rural Kenya. Data from well-designed prospective cohort studies in populations with unique cultural characteristics can supplement RCT data in recommending public health policy.
PMID: 17558336 [PubMed - indexed for MEDLINE]
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No protection to men
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Mor Z, Kent CK, Kohn RP, Klausner JD (2007) Benefit. PLoS ONE 2(9):
The study objective was to describe male circumcision trends among men attending the San Francisco municipal STD clinic, and to correlate the findings with HIV, syphilis and sexual orientation.
Methods and Findings. A cross sectional study was performed by reviewing all electronic
records of males attending the San Francisco municipal STD clinic between 1996 and 2005. The prevalence of circumcision over
time and by subpopulation such as race/ethnicity and sexual orientation were measured. The findings were further correlated
with the presence of syphilis and HIV infection. Circumcision status was determined by physical examination and disease
status by clinical evaluation with laboratory confirmation.
Among 58,598 male patients, 32,613 (55.7%, 95% Confidence
Interval (CI) 55.2–56.1) were circumcised. Male circumcision varied significantly by decade of birth (increasing between 1920
and 1950 and declining overall since the 1960’s), race/ethnicity (Black: 62.2%, 95% CI 61.2–63.2, White: 60.0%, 95% CI 59.46–
60.5, Asian Pacific Islander: 48.2%, 46.9–49.5 95% CI, and Hispanic: 42.2%, 95% CI 41.3–43.1), and sexual orientation (gay/
bisexual: 73.0%, 95% CI 72.6–73.4; heterosexual: 66.0%, 65.5–66.5).
Male circumcision may [or, equally, may not] have been modestly protective
against syphilis in HIV-uninfected heterosexual men (PR 0.92, 95% C.I. 0.83–1.02, P = 0.06) . [No correlations were found between circumcision and HIV or syphilis in any of the groups of men studied, but the paper tries its best to make it look as if they were]
From the Results:
Table 2. Percent circumcised in those with and without syphilis infection by HIV status and sexual orientation, as determined during male patient visits, San Francisco municipal STD clinic, 1996-2005. |
Sexual orientation | Syphilis infection | HIV-infected | HIV-uninfected |
| | | Circumcised % | (n/N) | PR* | (95% CI) | Circumcised % | (n/N) | PR | (95% CI) |
Heterosexual | Yes | 62.5 | (10/16) | 0.85 | (0.40-1.56) | 66.7 | (384/576) | 0.92 | (0.83-1.02) |
| | No | 73.8 | (1,050/1,423) | Ref. | | 72.4 | (36,290/50,128) | Ref. | |
Gay/ bisexual | Yes | 75.8 | (214/282) | 1.0 | (0.87-1.15) | 72.7 | (384/528) | 0.98 | (0.88-1.08) |
| | No | 75.4 | (15,910/21,090) | Ref. | | 74.6 | (34,210/45,869) | Ref. | |
*PR = Prevalence ratio of circumcision status by syphilis infection (Yes/No)
Table 2 shows the proportion of visits by circumcised men at the
San Francisco municipal STD clinic from 1996 through 2005 by
sexual orientation, syphilis and HIV infection status. There was a trend towards a protective effect of circumcision for syphilis
infection in heterosexual HIV-uninfected men and in a lesser extent in HIV-infected men. Among gay/bisexual men, no such protective effect was seen and also no association was found between circumcision status and HIV infection (71.1% circumcised
versus 72.2%, PR = 0.97, 95% CI 0.90-1.0, P =0.52). |
Conclusions. Male circumcision was
common among men seeking STD services in San Francisco but has declined substantially in recent decades. Male circumcision
rates differed by race/ethnicity and sexual orientation. Given recent studies suggesting the public health benefits of male
circumcision, a reconsideration of national male circumcision policy is needed to respond to current trends.
[And therefore Carthage must be destroyed. The conclusion does not follow at all from the data.
"A trend towards a protective effect" is weasel wording for no correlation.
Class | Prevalence of circumcision ratio Syphilis : No Syphilis |
Heterosexual | HIV- | 0.92:1 |
HIV+ | 0.85:1 |
Gay/Bisexual | HIV- | 0.98:1 |
HIV+ | 1.00:1 |
However, none of the ratios is statistically significant.
Considering HIV, in every row except the first, the percentage on the right (circumcised men with HIV) is greater than the percentage on the left (intact men with HIV), and in the first row, there are only six intact (heterosexual) men with HIV (and syphilis). Here is a different presentation of the same data:
Class | Prevalence of circumcision ratio HIV+ : HIV- |
Heterosexual | Syphilis | 0.94:1 |
No Syphilis | 1.02:1 |
Gay/Bisexual | Syphilis | 1.04:1 |
No Syphilis | 1.01:1 |
In all classes except the first, men with HIV are very slightly more likely to be circumcised than men without HIV, but in no class does the difference reach statistical significance. (And in the first class - because only six of the men with HIV were intact - if one more HIV+ man had been circumcised, that ratio would also have been greater than 1:1.)
There are other problems with this paper. According to its Table 1 there were 15,515 intact men, while according to Table 2 intact men paid only 14,409 visits to the clinic.
A published response to the paper
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No protection to men who have sex with men in London
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Circumcision Among Men Who Have Sex with Men in London, United Kingdom: An Unlikely Strategy for HIV Prevention
Abstract
Male circumcision is unlikely to be a workable HIV prevention strategy among London MSM, the current study suggests. The team undertook the research to explore attitudes about circumcision among MSM in London and to assess the feasibility of conducting research on circumcision and HIV prevention among these men. In May and June 2008, a convenience sample of MSM visiting gyms in central London completed a confidential, self-administered questionnaire. The information collected included demographic characteristics, self-reported HIV status, sexual behavior, circumcision status, attitudes about circumcision, and willingness to take part in research on circumcision and HIV prevention. Among the 653 participants, 29 percent reported they were circumcised. HIV prevalence among the MSM was 23.3 percent and did not differ significantly between circumcised (18.6 percent) and uncircumcised (25.2 percent) men (adjusted odds ratio=0.79; 95 percent confidence interval: 0.50-1.26). The proportion of participants reporting unprotected anal intercourse in the past three months was similar in the circumcised (38.8 percent) and uncircumcised (36.7 percent) groups (AOR=1.06; 95 percent CI: 0.72-1.55). The uncircumcised MSM were [much] less likely to think there were benefits to being circumcised compared to the circumcised men (31.2 percent vs. 65.4 percent, P<0.001). Just 10.3 percent of the uncircumcised men indicated a willingness to take part in research on circumcision as a strategy to prevent HIV transmission. “Most uncircumcised MSM in this London survey were unwilling to participate in research on circumcision and HIV prevention,” the authors concluded. “Only a minority of uncircumcised men thought that there were benefits of circumcision. It is unlikely that circumcision would be a feasible strategy for HIV prevention among MSM in London.”
Source
http://www.stdjournal.com
Date of Publication
10//2011
Author
Alicia C. Thornton; Samuel Lattimore; Valerie Delpech; Helen A. Weiss; Jonathan Elford
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Circumcision as a risk of HIV transmission
The Bagisu people of Eastern Uganda circumcise boys aged 12-18 years. The cultural practices associated with
circumcision are a risk to HIV transmission. HIV transmission awareness
programmes have been running in the local media but the message is mainly
perceived by urban, literate people. The researchers found it is hard to change the attitude of the
Bagisu towards their cultural circumcision practices despite the risks.
A. Kataami Moiti. Joint Clinical Research Centre, Kampala, Uganda
The Importance of education in addressing risk factors
associated with cultural circumcision practices among Bagisu
community, Uganda
Poster at the XV AIDS Conference in Bangkok, July 2004 [ThPeC7544]
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WebmedCentral EPIDEMIOLOGY 2011;2(9):WMC002206
Scarification and Male Circumcision Associated with HIV Infection in Mozambican Children and Youth
By Dr. Devon D Brewer
Abstract
Background: In sub-Saharan Africa, significant numbers of children with seronegative mothers are HIV infected. Similarly, substantial proportions of African youth who have not had sex are infected with HIV. These findings imply that some African children and youth acquire HIV through blood exposures in unhygienic healthcare, cosmetic care, and rituals. In prior research, male and female Kenyan, Lesothoan, and Tanzanian adolescents and virgins who were circumcised were more likely to be infected with HIV than their uncircumcised counterparts.
Methods: I examined the association between male circumcision, scarification, and HIV infection in Mozambican children and youth with data from the 2009 Mozambique AIDS Indicator Survey. I excluded from analysis children under age 12 who had HIV seropositive biological mothers. I coded children and youth as exposed to circumcision or scarification only if it had occurred within the prior 10 years.
Results: Circumcised and scarified children and youth were two to three times more likely to be infected with HIV than children and youth who had not been circumcised or scarified, respectively. Circumcision and scarification were each associated with HIV infection for both virgins and sexually experienced youth. Males circumcised by medical doctors were almost as likely to be infected as those circumcised by traditional circumcisers. Circumcision and scarification were also independently associated with HIV infection in males.
Conclusions: To determine modes of HIV transmission with confidence, researchers must employ more rigorous research designs than have been used to date in sub-Saharan Africa. In the meantime, Mozambicans and other Africans should be warned about all risks of blood-borne HIV transmission, including scarification and medical and traditional circumcision, and informed about how these risks can be avoided.
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No protection to Australians
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Australian and New Zealand Journal of Public Health, 35: 459–465. doi: 10.1111/j.1753-6405.2011.00761.x
Not a surgical vaccine: there is no case for boosting infant male circumcision to combat heterosexual transmission of HIV in Australia
Robert Darby, Robert Van Howe
Abstract
Objective: To conduct a critical review of recent proposals that widespread circumcision of male infants be introduced in Australia as a means of combating heterosexually transmitted HIV infection.
Approach: These arguments are evaluated in terms of their logic, coherence and fidelity to the principles of evidence-based medicine; the extent to which they take account of the evidence for circumcision having a protective effect against HIV and the practicality of circumcision as an HIV control strategy; the extent of its applicability to the specifics of Australia's HIV epidemic; the benefits, harms and risks of circumcision; and the associated human rights, bioethical and legal issues.
Conclusion: Our conclusion is that such proposals ignore doubts about the robustness of the evidence from the African random-controlled trials as to the protective effect of circumcision and the practical value of circumcision as a means of HIV control; misrepresent the nature of Australia's HIV epidemic and exaggerate the relevance of the African random-controlled trials findings to it; underestimate the risks and harm of circumcision; and ignore questions of medical ethics and human rights. The notion of circumcision as a ‘surgical vaccine’ is criticised as polemical and unscientific.
Implications: Circumcision of infants or other minors has no place among HIV control measures in the Australian and New Zealand context; proposals such as these should be rejected.
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Insufficient evidence of protection before the RCTs
A Cochrane Review of HIV-circumcision studies finds:
"Despite the positive results of a number of observational studies, there are not yet sufficient grounds to conclude that male circumcision, as a preventive strategy for HIV infection, does more
good than harm."
"Circumcision itself may be a proxy measure of the knowledge and behaviour learnt during initiation, when young men are taught about traditional sexual practices, including monogamy and penile hygiene."
"Selection bias was problematic in all studies, and results were potentially confounded by other risk factors for transmission of HIV such as sexual behaviour and religion. Circumcised and uncircumcised groups (in cohort and cross-sectional studies) and HIV-positive and HIV-negative groups (in case-control studies) were seldom balanced for all or most of the 10 risk factors that we identified as potential confounders prior to quality assessment."
- "Age
- Sexual behaviour
- Location of trial
- Religion
- Education, occupation, socio-economic status
- Sexual behaviour – measured by age at first intercourse, number of sexual
partners, contact with sex workers
- Any sexually transmitted infections
- Condom use
- Migration status, travel to different countries
- Other possible exposures, e.g. injection, blood transfusions"
"As HIV is related to sexual behaviour, which may in turn be partly determined by culture and religion, strong confounding factors in these studies seem likely."
"It is important to note that observational
studies, unlike R[andom] C[ontrolled] T[rial]s, can only adjust for known confounders, and only then if they are measured without error. The effect of unknown confounders may
well be operating in either direction within and across all of the included
studies."
The Medical Research Council of South Africa has a good summary of it.
|
Only cautious support after the RCTs
Another Cochrane review cautiously supported a protective effect:
Siegfried N, Muller M, Deeks JJ, Volmink J. Male circumcision for prevention of heterosexual acquisition of HIV in men. Cochrane Database of Systematic Reviews 2009, Issue 2. Art. No.: CD003362. DOI: 10.1002/14651858.CD003362.pub2
There is strong evidence that medical male circumcision reduces the acquisition of HIV by heterosexual men by between 38% and 66% over 24 months. Incidence of adverse events is very low, indicating that male circumcision, when conducted under these conditions, is a safe procedure. Inclusion of male circumcision into current HIV prevention measures guidelines is warranted, with further research required to assess the feasibility, desirability, and cost-effectiveness of implementing the procedure within local contexts.
While the Cochrane reviews are highly regarded, this one appears to have done no more than added in, at face value, the three RCTs, whose faults are detailed on another page.
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A warning against excessive reliance on RCTs
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BMC Medical Research Methodology 2011, 11:34 doi:10.1186/1471-2288-11-34
What counts as reliable evidence for public health policy: the case of
circumcision for preventing HIV infection
Reidar K Lie and Franklin G Miller
Abstract (provisional)
Background
There is an ongoing controversy over the relative merits of randomized controlled trials (RCTs) and non-randomized observational studies in assessing efficacy and guiding policy. In this paper we examine male circumcision to prevent HIV infection as a case study that can illuminate the appropriate role of different types of evidence for public health interventions.
Discussion
Based on an analysis of two Cochrane reviews, one published in 2003 before the results of three RCTs, and one in 2009, we argue that if we rely solely on evidence from RCTs and exclude evidence from well-designed non-randomized studies, we limit our ability to provide sound public health recommendations. Furthermore, the bias in favor of RCT evidence has delayed research on policy relevant issues.
Summary
This case study of circumcision and HIV prevention demonstrates that if we rely solely on evidence from RCTs and exclude evidence from well-designed non-randomized studies, we limit our ability to provide sound public health recommendations.
[The authors are at (excessive?) pains not to challenge the circumcision-HIV claims, but they point to many of the same holes in the RCTs that Intactivists do, and make the point that the second Cochrane review simply ignored all studies prior to the RCTs and hence the negative conclusion of the first Cochrane review.]
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Other studies showing no correlation, or a negative correlation between intactness and HIV.
Where circumcision doesn't prevent AIDS
Country | % of men circumcised | % HIV prevalence in | Adults | Circumcised men | Uncircumcised men |
Burkina Faso | 88 | 1.8 | 1.8 | 2.9 |
Cameroon | 93 | 5.5 | 4.1 | 1.1 |
Cote d'Ivoire | 96 | 4.7 | 2.8 | 3.8 |
Ethiopia* | 91 | 1.4 | 0.9 | 1.1 |
Ghana | 95 | 2.2 | 1.6 | 1.4 |
Kenya | 83 | 6.7 | 3.0 | 12.6 |
Lesotho | 49 | 23.5 | 22.8 | 15.2 |
Malawi | 20 | 11.8 | 13.2 | 9.5 |
Rwanda | 9 | 3.0 | 3.5 (2010 2.5) | 2.1 (2010 2.2) |
Swaziland | 8.1 | 25.9 | 21.8 | 19.5 |
Tanzania | 69 | 7.0 | 6.5 | 5.6 |
Uganda | 25 | 6.4 | 3.8 | 5.6 |
Source: National surveys, available at: www.measuredhs.com/countries/ |
* The HIV rate for Ethiopia is probably underreported, according to the UN. Circumcision is almost universal.
Swaziland, with its low circumcision rate and high HIV rate, is often cited as place where circumcision is urgently needed, but these figures show circumcision would do little good and might do harm.
A more recent survey, with more countries
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United States Agency for International Development (USAID) February 2009
LEVELS AND SPREAD OF HIV
SEROPREVALENCE AND ASSOCIATED
FACTORS: EVIDENCE FROM NATIONAL
HOUSEHOLD SURVEYS DHS COMPARATIVE
REPORTS 22
There appears to be no clear pattern of association between male circumcision and HIV prevalence. In 8 of 18 countries with data, as expected, HIV prevalence is lower among circumcised men, while in the remaining 10 countries HIV prevalence is higher among circumcised men ...
Findings from the 18 countries with data present a mixed picture of the association between male circumcision and HIV prevalence (Table 9.3). In eight of the countries (Burkina Faso, Cambodia, Côte d'Ivoire, Ethiopia, Ghana, India, Kenya, and Uganda), HIV prevalence is higher among men who are not circumcised, although the difference between circumcised and non-circumcised men is slight, except in Kenya, where the difference is substantial (HIV prevalence of 11.5 percent for non-circumcised men compared with 3.1 percent for circumcised men) (Figure 9.1). In 10 of the countries (Cameroon, Guinea, Haiti, Lesotho, Malawi, Niger, Rwanda, Senegal, Tanzania, and Zimbabwe) HIV prevalence is higher among circumcised men.
p123
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| Table 9.3. HIV prevalence among men age 15-49, by male circumcision |
| Male circumcision |
| Country/sex | No | Yes | Total |
| Burkina Faso 2003 |
| Male [%] | 2.9 | 1.7 | 1.9 |
| Number | 334 | 2,731 | 3,065 |
| Cambodia 2005 |
| Male [%] | 0.6 | 0.0 | 0.6 |
| Number | 6,517 | 138 | 6,656 |
| Cameroon 2004 |
| Male [%] | 1.3 | 4.3 | 4.1 |
| Number | 317 | 4,298 | 4,615 |
| Côte d'Ivoire 2005 |
| Male [%] | 3.5 | 2.8 | 2.9 |
| Number | 173 | 3,850 | 4,023 |
| Ethiopia 2005 |
| Male [%] | 1.2 | 0.9 | 0.9 |
| Number | 384 | 4,420 | 4,804 |
| Ghana 2003 |
| Male [%] | 1.7 | 1.4 | 1.5 |
| Number | 181 | 3,864 | 4,045 |
| Guinea 2005 |
| Male [%] | 0.0 | 1.0 | 0.9 |
| Number | 18 | 2,558 | 2,577 |
| Haiti 2005 |
| Male [%] | 1.9 | 3.9 | 2.0 |
| Number | 4,071 | 243 | 4,321 |
| India 2005/06 |
| Male [%] | 0.4 | 0.2 | 0.4 |
| Number | 40,340 | 5,818 | 46,506 |
| Kenya 2003 |
| Male [%] | 11.5 | 3.1 | 4.6 |
| Number | 475 | 2,372 | 2,851 |
| Lesotho 2004/05 |
| Male [%] | 15.4 | 23.4 | 19.2 |
| Number | 1,046 | 951 | 2,001 |
| Malawi 2004 |
| Male [%] | 9.4 | 13.2 | 10.2 |
| Number | 1,906 | 500 | 2,405 |
| Niger 2006 |
| Male [%] | 0.0 | 0.8 | 0.8 |
| Number | 14 | 2,841 | 2,856 |
| Rwanda 2005 |
| Male [%] | 2.1 | 3.8 | 2.3 |
| Number | 3,908 | 418 | 4,348 |
| Senegal 2005 |
| Male [%] [%] | 0.0 | 0.5 | 0.5 |
| Number | 56 | 3,124 | 3,183 |
| Tanzania 2003/04 |
| Male [%] [%] | 5.6 | 6.5 | 6.3 |
| Number | 1,529 | 3,463 | 4,994 |
| Uganda 2004/05 |
| Male [%] [%] | 5.5 | 3.7 | 5.1 |
| Number | 5,613 | 1,858 | 7,477 |
| Zimbabwe 2005 |
| Male [%] | 14.2 | 16.6 | 14.5 |
| Number | 5,235 | 597 | 5,848 |
| Note: HIV prevalence estimates for ‘not circumcised’ men for Guinea and Niger are based on small numbers of cases |
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... data has since become available for Mozambique and Zambia. In both cases, HIV prevalence is higher among those uncircumcised. Data also became available for Swaziland, which showed that HIV prevalence is higher among those who are circumcised.
Second, in the case of Tanzania, the earlier USAID report states that prevalence is higher among those who are circumcised. A more recent study indicates the opposite, with HIV prevalence being 3.7% among the circumcised and 6.4% among the uncircumcised.
Third, of the 14 countries where male circumcision is being promoted (Botswana, Ethiopia, Kenya, Lesotho, Malawi, Mozambique, Namibia, Rwanda, South Africa, Swaziland, Tanzania, Uganda, Zambia and Zimbabwe), there is no recent DHS data about male circumcision and HIV prevalence for 3 of them (Botswana, South Africa and Namibia). Of the 11 countries where there is data, 5 of them have higher HIV prevalence among the circumcised (Lesotho, Malawi, Rwanda, Swaziland and Zimbabwe) and 6 have higher HIV prevalence among the uncircumcised (Ethiopia, Kenya, Mozambique, Tanzania, Uganda and Zambia).
Those who support circumcision argue that at least in Lesotho and Malawi, partial circumcision is practiced, which may explain the results in those two countries. Also in Rwanda, the data indicates that if you look only in urban areas, circumcision is actually partially protective (even though in the country as a whole, it appears not to be). [More data-mining.]
- LSTM1 in ZimEye, December 29, 2011
[Clearly the results are still mixed, with nothing like the clear correlations you would expect if circumcision really did reduce HIV by anything like "60%"]
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Between Correlation and Recommendation
"Circumcision status should be viewed as a proxy for other aspects of human behavior. Unless one can control for these aspects, one cannot draw reliable conclusions about the causative status of the presence or absence of a foreskin on the course of medical disease processes."
- Dr Anne Laumann in a letter to Archives of Dermatology
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Several intermediate steps need to be taken, between the association shown in some (not all) studies and recommending general circumcision as a preventative measure. Married men in Africa have a higher rate of HIV infection than single men, but so far no one has called for the abolition of marriage. The proofs of links to circumcision and to marriage are similar, but first
- the association needs to be clearly established (in the case of circumcision, some think it has been, but many think it has not). Then
- a case for causality needs to be made (it falls short). Then
- a cost-utility estimate needs to be done to see if it is feasible, and, if so,
- under what conditions. Then
- a randomised trial needs to be performed. Finally, if all of those items fall into place, only then can one reasonably
- make the call for universal or selective circumcision.
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J Med Ethics 2010;36:798-801 doi:10.1136/jme.2010.038695 HIV/AIDS and circumcision: lost in translation Marie Fox and Michael Thomson
Abstract
In April 2009 a Cochrane review was published assessing the effectiveness of male circumcision in preventing acquisition of HIV. It concluded that there was strong evidence that male circumcision, performed in a medical setting, reduces the acquisition of HIV by men engaging in heterosexual sex. Yet, importantly, the review noted that further research was required to assess the feasibility, desirability and cost-effectiveness of implementation within local contexts. This paper endorses the need for such research and suggests that, in its absence, it is premature to promote circumcision as a reliable strategy for combating HIV. Since articles in leading medical journals as well as the popular press continue to do so, scientific researchers should think carefully about how their conclusions may be translated both to policy makers and to a more general audience. The importance of addressing ethico-legal concerns that such trials may raise is highlighted. The understandable haste to find a solution to the HIV pandemic means that the promise offered by preliminary and specific research studies may be overstated. This may mean that ethical concerns are marginalised. Such haste may also obscure the need to be attentive to local cultural sensitivities, which vary from one African region to another, in formulating policy concerning circumcision.
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A Vaccine? Hardly!
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Australian Doctor November, 2005
Circumcision equal to a vaccine for HIV
by Rebecca Jenkins
CIRCUMCISION offers the same level of protection against HIV infection in heterosexual men as a highly effective vaccine, according to a landmark study. In the first randomised controlled trial of its kind, researchers found circumcision provided 60% protection against the virus, confirming the results of a large body of observational studies. |
 
A vaccine of high efficacy is expected to offer long-term protection of 95% or above.
Smallpox was eradicated with such a highly efficient vaccine. If control
of tetanus, measles, and poliomyelitis has been largely achieved in the
world, it has been a result of high-efficacy vaccines. ... A 96%-efficient measles vaccine
means that 96% of vaccinated persons exposed to measles are indeed
protected against infection. Protection lasts for many years, and
revaccination permits dealing with loss of immunity over time. What Auvert
and colleagues show is ... a 60% reduction in disease
incidence over an 18-month period among circumcised men compared with
uncircumcised men with similar exposure. To our knowledge, this does not
mean that those men are really "protected" against HIV, especially in the
case of repeated exposure. It simply means "reduced risk," or reduced
probability of contamination.
- Michel Garenne, Male Circumcision and HIV Control in Africa
In a text for upper division and/or graduate study of immunology, a table
gives the percentage of reduction obtained by vaccines for the diseases modern societies associate with successful
immunization programs.
Smallpox, diphtheria, and polio vaccinations resulted in 100% reduction
of incidence. Vaccination against measles, Mumps, and rubella (German
measles) resulted in >99% reduction of incidence. Tetanus (lockjaw) was
reduced by more than 98%; Pertussis (whooping cough) by more than 87%.
(No vaccines that reduced incidence by as little as 70% were
included in the table.)
- Kindt, Thomas J, Goldsby, R.A., and Osborne, B.A. (Kuby) Immunology (6th
Ed), New York: W.H. Freeman, 2007. [Kindt - NIH, Goldsby - Amherst
College, Osborne - UMass, Amherst]
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A Solution Looking For A Problem
The question arises, why have so many studies been done apparently looking for this correlation (and prematurely making the recommendation)? For over a hundred years, circumcision has been a solution looking for a problem, and the problem has typically been the most frightening disease (or "disease") of the day -
- "masturbation insanity" in the 19th century,
- then tuberculosis,
- Sexually Transmitted Diseases (then called Venereal Disease or VD) after World War I,
- penile cancer in the 1930s, and
- cervical cancer in the 1950s, when cancers were terrifyingly untreatable,
- Urinary Tract Infections from 1982 onward,
- and now HIV.
Today's calls are just the latest in a long series, and no better founded than those.
Ethics
As ethicist Dr Margaret Somerville (Gale professor of law and a professor in the faculty of medicine at the McGill Centre for Medicine, Ethics and Law) says:
"...even assuming that reducing the risk of HIV transmission could be a justification for infant male circumcision, this justification would not be available until it became at least more likely than not that circumcision would reduce the risk of HIV transmission.
"...even assuming that circumcision could help to protect against HIV infection, it would not be necessary to carry it out on unconsenting infants. One could wait until the person was about to become sexually active and could decide for himself.
"...one is ethically required to use the least harmful, least invasive means of achieving a good, the achievement of which involves harm. Consequently, a surgical intervention aimed at preventing the spread of HIV could only be justified if there were no other reasonable way to achieve this. And, even if circumcision helped to
protect people in developing countries from the spread of HIV, we would not be justified in carrying this out for this purpose in developed countries, where other, better means of protection are much more readily available."
- The Gazette, Montreal, October 24, 1998, pB6 |
the Role of the Mucosa
Circumcisionists have added to the meme-pool the "explanation" that the foreskin has a peculiar role in HIV transmission. (This focuses on the Langerhans cells, yet on scanty evidence and through contradictory mechanisms.) Yet the genital mucosa have an important role in preventing transmission:
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Models of Protection Against HIV/SIV: Avoiding AIDS in Humans and Monkeys
Edited by Gianfranco Pancino, Guido Silvestri and Keith Fowke
Chapter 5 – The Genital Mucosa, the Front Lines in the Defense Against HIV
T. Blake Ball, Kristina Broliden
Summary
Mucosal sexual transmission of HIV now accounts for the majority of transmission worldwide, and occurs at the genital tract. However, relative to what is known about systemic correlates of protection, less is known about innate and adaptive immune responses capable of affecting HIV transmission at this site. The protective efficacy of immune mechanisms at the genital tract, especially the female genital tract, has been estimated to stop the vast majority of HIV transmission across an intact and uninflamed mucosal surface, indicating a protective efficacy of almost 99 percent – much greater than any biomedical intervention described to date. There is considerable evidence that individuals who appear to be naturally protected from HIV infection may be protected from HIV infection at this site. In this chapter we will discuss the physiologic features of the genital mucosa, the underlying cells susceptible to HIV transmission and replication, and the role of innate and adaptive immune responses at this site in protecting against HIV infection in highly HIV-exposed, uninfected subjects.
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"Dry Sex"
Meanwhile, an explanation seems to be to hand: "dry sex" - the use by women of herbal and other astringents to dry their vaginas.
Wet, Dry, Man, Woman: Heterosexuals and Anal Sex
formerly at http://hivinsite.ucsf.edu/
Wet/Dry and Tight/Loose
DH: We ... encountered a notion of "dry sex" that appears to be shared in Haiti, the
country with which the Dominican Republic shares an island, as well as
various parts of Africa. It's complex and it varies from place to place,
but the basic idea is that sex should be very tight and should be dry. In
the Dominican Republic, I couldn't help but begin to think that maybe that
was part of the appeal for anal sex, both bisexual male anal sex and
heterosexual anal sex. Particularly if, as you say, women have given birth
and so on. A lot of women there and in countries like Brazil will have
operations to tighten the vaginal opening. There's actually a surgical
procedure in the Dominican Republic that translates as "the cut that makes
the husband happy." It's basically a tightening of the vagina after the
woman has given birth.
Given this notion that sex should be tight, there's potentially an
interaction with the foreskin there, because we seem to mainly find
dry sex practices in areas where most men are not circumcised. One
explanation may be that circumcised men don't have the lubricative
mechanism of the foreskin rolling back and forth across the glans.
Presumably, it would be quite painful and uncomfortable for most men to
have dry sex if they are circumcised. But uncircumcised men in the
Domincan Republic and in parts of Africa commonly report tearing and
bleeding of the foreskin during dry sex. ...
| "Dry sex practices appear to be primarily restricted to certain predominately non-male[-]circumcising regions of eastern and southern Africa, including many of the countries reporting the world's highest HIV seroprevalence (for example, Zimbabwe, Botswana, Zambia, Malawi). Presumably, such practices would appear to be less appealing to the drier (non-prepucial secreting) circumcised males of western Africa or other regions. Reportedly, very few men in the Dominican Republic or Haiti [where dry sex is also widely practised] have been circumcised . . . ."
Halperin, Daniel T. Dry sex practices and HIV infection in the Dominican Republic and Haiti. Sexually Transmitted Infections 1999; 75:445-446.
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The role of delayed washing after sex
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Have WHO and UNAIDS gotten the wrong message from studies of circumcision to reduce men's risk for HIV? April 16, 2012
16 April 2012
By David Gisselquist
In 2003-06, a study team funded by the US National Institutes of Health (NIH) recruited HIV-negative intact (uncircumcised) men in Rakai, Uganda, circumcised some, and then followed and retested both circumcised and intact men to see who got HIV.[1] The most widely reported data from this study say that men in the intervention (circumcised) group got HIV at the rate of 0.66% per year vs. 1.33% per year for men in the control (intact) group. These data have been used to motivate efforts to circumcise 20 million African adults by 2015 as well as to introduce routine infant circumcision.
Circumcise vs. wait and wipe
However, other data from the same study show a more effective, less dangerous, less culturally intrusive, and less expensive option for intact men to protect themselves from HIV after sexual contact – simply waiting at least 10 minutes after coitus before doing anything to clean one’s penis, and then just wiping it with a dry cloth, without water (Table). (Condom use reliably protects men from acquiring HIV from sexual partners; this note discusses waiting and wiping as an alternative to circumcision, not as an alternative to condom use.)
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Alcohol
One confounding factor that the circumcisionists haven't noticed (because they weren't looking), is alcohol usage. An eight-year study in Uganda has shown a correlation between alcohol consumption and HIV infection (because people who have been drinking are less likely to practise safe sex). Islam prohibits alcohol and also prescribes circumcision. It is at least as reasonable that the prohibition as the prescription protects against HIV.
Circumcisionists are fond of claiming that their statistics have been "adjusted" to correct for this kind of confounding error, but Ted Goertzel argues that such "adjustments" are just an attempt to blind us with science.
Sexual selection
People don't have sex with just anyone, they tend to do so within their own social groups, so HIV stays within social groups. (The clearest case is that in the US, gay men have sex with gay men, heterosexual men with heterosexual women. So once it started with them, HIV would have spread mainly among gay men regardless of other factors.) So in Africa, if HIV first spread in societies where men were intact, it would continue to do so, and not in societies where men were cut.
Female Genital Mutilaton
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Abstract: Female circumcision and HIV infection in Tanzania: for better or for
worse? Stallings R.Y, Karugendo E. (PowerPoint)
Introduction: ...The authors sought to
explain an unanticipated significant crude association of lower HIV risk among circumcised women [R{isk} R{atio}=0.51; 95% C{onfidence} I{nterval} 0.38,0.70] in a recent survey by examining other factors which might confound this crude association.
Methods: Capillary blood was collected ... from a
nationally representative sample of women age 15 to 49 during the 2004
Tanzania Health Information Survey. Eighty-four percent of eligible women
gave consent for their blood to be anonymously tested for HIV antibody.
Interview data was linked ... to final test results for 5753
women. The chi-square test of association was used to examine the
bivariate relationships between potential HIV risk factors with both
circumcision and HIV status. Restricting further analyses to the 5297
women who had ever had sexual intercourse, logistic regression models were
then used to adjust circumcision status for other factors found to be
significant.
Results: By self-report, 17.7 percent of women were
circumcised. Circumcision status varied significantly by region, household
wealth, age, education, years resident, religion, years sexually active,
union status, polygamy, number of recent and lifetime sex partners, recent
injection or abnormal discharge, use of alcohol and ability to say no to
sex. In the final logistic model, circumcision remained highly significant
[O{dds} R{atio}=0.60; 95% C{onfidence} I{nterval} 0.41,0.88] while adjusted for region, household wealth, age, lifetime partners, union status, and recent ulcer.
Conclusions: A lowered risk of HIV infection among circumcised women was not attributable to confounding with another risk factor in these data. Anthropological
insights on female circumcision as practiced in Tanzania may shed light on
this conundrum.
Will there be Randomised Controlled Trials of 3000 HIV-negative women, where 1500 are circumcised and they see how many seroconvert - followed by calls for mass circumcision of women to prevent the spread of HIV? Of course not.
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Kanki et al. reported that, in Senegalese prostitutes, women who had undergone female genital cutting had a significantly decreased risk of HIV-2 infection when compared to those who had not.
Kanki P, M'Boup S, Marlink R, et al. "Prevalence and risk determinants of human immunodeficiency virus type 2 (HIV-2) and human immunodeficiency virus type 1 (HIV-1) in west African female prostitutes Am. J. Epidemiol. 136 (7): 895-907. PMID |
The correlation one way between FGM and MGM is almost 100%. That is, females are circumcised only if males are. So if FGM reduced the incidence of HIV, it could be mistaken for an effect of MGM.
Only one exception has been found, the Pokot tribe in Kenya - but they used to circumcise males (and have begun to again - to prevent HIV...).
Wife Inheritance
Among the Luo people of Kenya (who do not practise circumcision), when a man dies, his wife is "inherited" by his brother. She is
required to have intercouse with him, and that intercourse must be
unprotected. Otherwise the husband's spirit is not free, and the wife is
not free to remarry. The rate of HIV among
people tested in that region was 2/3. One man said it makes no difference if they know
the woman is HIV positive. They do not believe AIDS is caused by a virus:
"If a man dies, it is because he has done something wrong."
There can be no doubt that wife-inheritance is a potent factor in HIV
transmission - especially where the death rate from HIV is high: it's a
vicious circle. Wife inheritance is seldom if ever mentioned as a confounding factor in studies of HIV transmission.
If there should be a
correlation between intactness and wife-inheritance, or between
circumcision and the shunning of wife-inheritance, that might go a long
way toward explaining the supposed intactness-HIV link.
- A BBC story 18 November 2003.
- The Washington Post November 8, 1997
- Christianity Today August 28, 2000
"The Luo people are often polygamous, and several widows may be
inherited by a single family member. Another element of the tradition is
the practice of holding a "cleansing" ritual in which the widow has sex
with an outsider before being given to her brother-in-law or other family
member."
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Heterosexual transmission, Europe vs the United States
A common criticism of "Circumcision prevents HIV" is "But HIV is very common in the US, where circumcision is prevalent." A common reply from the pro-circumcision lobby is that HIV is primarily transmitted homosexually in the US, heterosexually in Africa, and anal receptivity of HIV is unaffected by circumcision. This can be countered by comparing the United States with Europe, where homosexual and heterosexual rates of transmission are comparable, but circumcision rates are very different. The US proves to have a much higher rate of HIV than Europe, and a disproportionate rate of male to female transmission.
Advocates of circumcision then have to put considerable spin on the statistics. For example, Bailey and Halperin write:
Remarkably, there is consistent evidence that female-to-male HIV transmission, compared with male-to-female transmission, is much higher in Europe than in the USA . . . Data from the European Multicenter Partners Study and comparable research from the USA suggest that the ratio of female-to-male transmission (compared with male to female transmission) is about 10 fold higher in Europe.3
[3 De Vincenzi I. Heterosexual transmission of HIV. JAMA 1992; 267:
1919.]
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The implication is that intact European men are being infected with HIV at an alarming rate compared to their circumcised counterparts in the US.
This is assisted by the straightforward but false interpretion that the rate of female-to-male transmission is higher in Europe. Bailey and Halperin actually mean the ratio of the ratios of (female-to-male vs male-to-female in) Europe vs (female-to-male vs male-to-female in) the US.
Yet if the four sets of data are compared, standardising the US total to 100, M-to-F amounts to 95, F-to-M to 5, and in Europe, M-to-F 20 and F-to-M 10. So Halperin's extraordinary ratio is (10/20)/(5/95) = (1/2)/(1/19) = 9.5
(In exact figures,(10.10/20.20)/(4.76/95.24)=10.0)
Expressed pictorially:
Clearly, what needs to be explained is not a high female-to-male HIV transmission rate in Europe, but the high male-to-female rate in the US. Could the reason be the rougher action of dry, circumcised US penises, creating micro-tears on US women's vaginal walls? Perhaps not, perhaps it is is the different strains of HIV prevalent in the US and Europe, but this kind of difference between fact and interpretation illustrates that simple correlations do not necessarily translate into simple solutions.
"Russian Roulette with two bullets rather than three"
Male circumcision and HIV infection
For several years, researchers have been debating the relationship
between male circumcision and HIV. Several studies have indicated
that circumcised men are less likely to become infected with HIV than
uncircumcised men. However, because circumcision is usually linked to
culture or religion, it has been argued that the apparent protective
effect of the procedure is likely to be related not to removal of the
foreskin but to the behaviours prevalent in the ethnic or religious
groups in which male circumcision is practised. In addition, some
researchers have assumed that any association between circumcision
and HIV must be complicated by the presence of other sexually
transmitted infections, which have been found to be more common among
uncircumcised men.
Clearly, the correlations are not straightforward. In the higher
income countries, the rates of HIV infection among men who have sex
with men do not vary greatly even though the circumcision rates do:
few men in Europe and Japan but four-fifths of men in the United
States are circumcised. In Africa, however, circumcision seems to
confer some protection. A study in Nyanza Province, Kenya, among men
from the same ethnic group, the Luo, found that one-quarter of
uncircumcised men were infected with HIV, compared with just under
one-tenth of circumcised men. The protective effect remained even
after other factors, such as sexual behaviour and sexually
transmitted infections, had been taken into account. A study of
over 6800 men in rural Uganda has suggested that the timing of
circumcision is important: HIV infection was found in 16% of men who
were circumcised after the age of 21 and in only 7% of those
circumcised before puberty. A recent review of 27 published studies
on the association between HIV and male circumcision in Africa found
that, on average, circumcised men were half as likely to be infected
with HIV as uncircumcised men. When African men with similar
socio-demographic, behavioural and other factors were compared,
circumcised men were nearly 60% less likely than uncircumcised
men to be infected with HIV.
Even though the weight of evidence increasingly suggests that
circumcising men before they become sexually active does provide
some protection against HIV, the practical implications for AIDS
prevention are not obvious. Circumcision, where it is practised,
usually has links to religious or ethnic identities and life-cycle
ceremonies, and may customarily be done after puberty. If the same
scalpel were used without sterilization on a number of boys, this
could actually contribute to the transmission of HIV. Finally, if
circumcision were promoted as a way of preventing HIV infection,
people might abandon other safe sexual practices, such as condom
use. This risk is far from negligible - already, rumours abound in
some communities that circumcision acts as a "natural condom". A sex
worker interviewed in the city of Kisumu in Kenya summed up this
misconception, saying: "I can sleep with circumcised men without a
condom because they don't carry a lot of dirt on their penis". While
circumcision may reduce the likelihood of HIV infection, it does not
eliminate it. In one study in South Africa, for example, two out of
five circumcised men were infected with HIV, compared with three out
of five uncircumcised men. Relying on circumcision for protection is,
in these circumstances, a bit like playing Russian roulette with
two bullets in the gun rather than three. [...assuming the gun has only five chambers - or, if it had the more usual six, 2.4 bullets rather than 3.6.]
- Report on the global HIV/AIDS epidemic
UNAIDS, June 2000 A large file, >275KB.
In the wake of three incomplete Random Controlled Tests of circumcision, the head of UNAIDS, Dr Peter Piot, has chosen to forget these wise words.
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A British survey of gay men found slightly more of the circumcised men were HIV-positive.
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Know
the score
Findings from the
National Gay Men’s
Sex Survey 2001
David Reid
Peter Weatherburn
Ford Hickson
Michael Stephens
...
Introduction and methods
1.1 CONTENT OF THE REPORT
This research report outlines the main findings of Vital Statistics 2001 – which was the fifth annual national Gay Men’s Sex Survey (henceforth GMSS). The survey was carried out during the summer of 2001 by Sigma Research in partnership with 73 health promotion agencies across England
and Wales.
...
Chapter 2 gives a brief description of the sample of 14,616 men living in England and Wales who either had sex with another man in the last year or expected to have sex with a man in the future.
...
1.2 BACKGROUND TO THE FIFTH NATIONAL GAY MEN’S SEX SURVEY
The Gay Men’s Sex Survey uses a short self-completion questionnaire to collect a limited amount of information from a substantial number of men. ...
1.3 PRIDE EVENTS: RECRUITMENT DATES, EVENTS AND RETURNS
Recruitment occurred at seven community-based events in the summer of 2001. ...
4.5 CIRCUMCISION
It has been suspected for some time that when uninfected men are insertive in UAI with positive men, whether or not the uninfected man is circumcised has a bearing on the probability of HIV transmission occurring. The hypothesis is that the cells of the fore-skin are more susceptible to infection by HIV and therefore circumcision has a protective function.
Men were asked Are you circumcised? and were asked to tick No, Yes or Don’t Know. Overall, 0.9%
said Don’t know by which we think they mean they do not know the word rather than not knowing whether they have a foreskin. Excluding this small group, 22.1% of men indicated that they were circumcised. The proportion rose with increasing age, from 16.1% among the under 20s, through 18.8% (in the 20s), 21.3% (in the 30s), 24.8% (in the 40s) and 40.2% among the over 50s.
Circumcision also significantly varied by ethnicity, being highest among Bangladeshi men (100%, 5/5), Pakistani men (97.5%, 39/40), other Asian men (77.3%, 68/88) and Black African men (76.1%, 35/46). Of all sixteen ethnic groups, White British men had the lowest level of circumcision (18.7%, 2201/11764).
If circumcised men are less likely to acquire HIV than men with foreskins, then we should expect fewer of the circumcised men to have tested positive than the men with a foreskin. However, more of the circumcised men had tested positive for HIV (6.1%) than had those with a foreskin (5.0%). This small but significant difference is in the opposite direction than predicted if foreskins are contributing to transmission, and was observed in all ethnic groups and across the age range.
The survey found no evidence to support the adoption of ‘the proportion of HIV uninfected men who are not circumcised’ as a population level target for HIV prevention programmes for gay and
bisexual men. [... let alone evidence to support the promotion of circumcising anyone]
[The only possible confounder remaining is selection bias. The results would not reflect the actual position if circumcised men who have HIV (and know it), or intact men who don't, are more likely to take the survey than intact men who have HIV (and know it) or circumcised men who don't, but it is very hard to see why that might be.
Only a small proportion of these men with HIV would have been infected trans-penilely, compared to the proportion infected tran-anally, so the small surplus of those HIV-positive men who are circumcised should not be taken as suggesting that circumcision makes HIV-infection more likely.]
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The hazards of unblinded studies
"Scientists must constantly be on guard against this sort of self-deception [picking and choosing data to agree with the preconception that electromagnetic fields, as from power lines, cause leukaemia]. Unless studies are carefully designed to avoid it, the biases of the epidemiologist have a way of creeping into the results. To minimize the opportunity for bias, scientists rely on double-blind studies. An independent researcher might be given a list including both the homes of victims of childhood leukemia and an equal number of addresses of nonvictim children matched in age, gender, race, family income, etc., but without any indication of which are which. Without knowing which were the homes of victims and which were "controls," the researcher would rate them by whatever criteria were used to estimate the field strength. Someone else would then apply the key after the judgments were made.
[Double-blinding a study involving circumcision is hardly practicable, but much more could have been done to make the circumcised experimental groups and the intact control groups equivalent.]
But even if the study had been double blind, a "risk ratio" of only three for a rare disease such as childhood leukemia would be regarded by many epidemiologists as barely credible. The risk ratio for lung cancer from smoking, for example, is well over thirty^ that is, a 3,000 percent increase in the incidence of lung cancer among smokers. Yet it took years of checking and rechecking the figures, as well as a highly plausible mechanism in terms of known carcinogens in tobacco smoke and, finally, confirming laboratory studies on animals before the cancer link was firmly nailed down."
- "Voodoo Science" by Robert Park, pp 150-1
"The estimated reduction in the relative risk of infection with HIV [between circumcised and intact men in the Kenyan and Ugandan trials] was 51% (unadjusted modified intention-to-treat analysis) to 55% (as-treated analysis)."
Editorial comment in The Lancet.
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Related pages:
External links:
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