5 June 2006
Circumcision And HIV
by Paul A.
Circumcision has sometimes been described as a solution in search of a problem. In the mid-19th century the problem was masturbation. Towards the end of that century it was syphilis. In the 1930s it was penile cancer. In the 1950s it was cervical cancer. 1980s - urinary tract infections. And let's not forget phimosis, balanitis and getting your dick caught in your zipper. It seems that with the passing of time the purported problems have gotten more trivial. Small wonder then that circumcision is on the wane. But suddenly, there's a big problem - AIDS. Several eminent scientists and medical researchers have determined that a link exists between circumcision status and the rate of HIV transmission and they are urging universal infant circumcision to help combat the disease. Could circumcision supporters have finally found the mother of all problems for their solution? Regrettably, the issue is so enmeshed in emotion and advocacy that it's hard to know where the truth lies.
Let's start with the evidence. Several studies carried out in Africa have found a positive correlation between HIV infection and non-circumcised status (notably, some studies have found a negative correlation but they're in the minority). None of these studies are flawless, however. In some cases the sample size is too small, in some the methodology is suspect and in others the logical inferences are unsupported by the evidence. That doesn't mean these studies are without merit. In the best of situations it's very difficult to conduct a controlled experiment with living human beings. People lie. People change their behavior. People move, quit, die and worst of all for experimenters – people have rights. An "ideal" experiment would be to randomly select a large sample of uncircumcised, non-HIV positive participants, circumcise half of them, force them all to repeatedly have sex with HIV infected partners, then conduct tests to see which group (circumcised or uncircumcised) has the highest rate of infection. That would be definitive. This is the only way we could confidently assert that a correlation exists. Alas, any conclusions drawn from any study that falls short of this "ideal" will have to be taken with at least some degree of analytic skepticism.
The potential failings are varied and cumulative. Take something as simple as defining the variable. Circumcisions and the reasons for circumcision differ from one tribe to the next. Muslims tend to circumcise their males in early adolescence. Other cultures circumcise just prior to marriage. Some remove the entire foreskin. Others just take a little nip leaving the prepuce largely intact. Assuming there is something about the foreskin that renders its possessor prone to HIV infection, then the amount of foreskin remaining becomes an important consideration in itself.
And what about the other variables? Besides circumcision status we have age, occupation, current health status, frequency of sex, sexual preference – and I'm not just talking homosexual versus heterosexual. The type of sexual activity varies greatly between individuals and cultures. Some men use prostitutes. Others have a girlfriend in every town. Some guys are even faithful to their wives. Some African men like "dry sex" where the woman uses herbs as astringents to help contract the vaginal passage. Consequently, lubrication is lost, allowing for greater friction and micro-tearing. Because micro-tearing is thought to be responsible for much HIV transmission, any study that fails to account for it is gonna be skewed.
And even if one could isolate every variable and still detect a strong correlation, one could not be sure that it indicated a causal effect. Some of the early studies found a positive correlation between non-circumcision and HIV status based on a geographical analysis of Africa. Regions with high circumcision rates tended to have lower rates of HIV transmission. The obviously flaw here is that the regions with high circumcision rates tend to be Muslim and one can assume Muslims would have a different and probably more restrictive view of what constitutes acceptable sexual behavior than their animist/uncircumcised counterparts. Indeed, if one were to apply the same geographic methodology to the developed world one would come to the opposite conclusion. The country with one of the highest rates of circumcision (the U.S.) also has one of the highest rates of HIV infection.
So does that mean we should just give up? Hell no. Even if we can never know the absolute truth we can still get within range. Enough studies have been conducted and enough multi-variant, meta-analytical statistical mumbo jumbo has been performed over the years that there appears to be at least some correlation between the possession a foreskin and susceptibility to HIV infection. Estimates vary widely but from what I've read, if you stood me up at the gates of hell and made me guess, I'd say that all things being equal, having a foreskin makes you between 1.5 and 2 times more susceptible to acquiring HIV. If you accept that this is true (you'd be a sucker - it's a guess, remember?) then the next question to ask is why? What is it about foreskins that facilitates the transmission of HIV?
One theory is that the relationship isn't causal. It's covariant. Genital ulcers associated with herpes simplex 2 (HSV-2) are widely regarded as transmission windows for HIV. Genital ulcers tend to be located on the foreskin; ergo correlation. Several epidemiologists have suggested that HIV transmission could be significantly reduced by treating for HSV-2. Another theory is that the foreskin and smegma are basically so gucky that if anything is likely to go wrong, it's likely to be there. In the words of Gerald N. Weiss M.D., perhaps the foremost apologist for circumcision, smegma is "composed of dead cells and secretions of the inner skin layer along with urine... and prostatic and testicular secretions. These excretions and secretions can lead to infections, stone formation and malignancy." Fair enough. But does that make smegma a conduit for HIV? Not necessarily. A much more likely candidate would be the structure of the foreskin itself. Researchers have determined that foreskin contains a high concentration of what are known as Langerhan's cells. Langerhan's cells function as part of the immune response system. They act as conduits to the lymphatic system where T-cells are produced. T-cells are one of the body's main defenses against infection and these are the very cells that HIV has evolved to infect. As a result, a surplus of Langerhan's cells predisposes a tissue to HIV infection. Interestingly, the aforementioned Dr. Weiss found that the inner mucosal linings of the infant prepuce contain a deficiency of Langerhan's cells. Ironically, Weiss presented this as evidence that the prepuce was inherently vulnerable to infection (this guy really didn't like foreskins). It's been suggested that the lack of Langerhan's cells in infants (assuming Weiss is correct) may be due to the fact that the infant foreskin has yet to retract and be exposed to pathogens.
So if there's a correlation between foreskins and HIV - and there's a good scientific rationale why this should be so - shouldn't we start lopping off foreskins pronto? The answer, I think, is no, for a number of reasons. Besides the obvious difficulties with logistics, the first and foremost reason is that circumcision will not prevent HIV transmission. It will at best reduce the likelihood of transmission by half, so it's like playing Russian roulette with 2 bullets instead of three. I'd rather play with two bullets myself, but the trouble comes when those who submit to the operation think the chamber's been emptied and go off firing their gun all over the place. Studies have shown this is a common misperception of those who have undergone the operation. Hell, it was probably part of the sales pitch to get them to submit in the first place. It's easy to see how such a program could seriously backfire. Secondly, unless strict antiseptic procedures are followed (not always a given in countries lacking a sound medical infrastructure), the act of mass circumcision could actually facilitate the spread of HIV. The third reason is an ethical one. In the words of ethicist Margaret Sommerville: "One is ethically required to use the least harmful, least invasive means of achieving a good outcome." Does the pay-off (reduced risk of transmission – if it worked), equal or surpass the loss? And more to the point, is it the least invasive means of achieving a good outcome? Not by a long shot. Much better means of prevention are education, lifestyle counseling and CONDOMS. Outside of abstinence and mutual fidelity, condoms are as close as we're ever going to get to a revolver with no bullets in it.
Unfortunately, much of the funding for fighting AIDS is currently being funneled through religious organizations that discourage the use of condoms. According to them, abstinence and fidelity are the answer. With abstinence and fidelity condoms aren't necessary. So the old A-B-C (Abstinence, Be faithful, Condoms) prevention focus only goes up to B at the current time.