NORM MUNDHENK, a linguist working in Papua New Guinea, recently stumbled on
an odd phenomenon. He heard a story about young men in a dormitory at the local
technical college who had all asked to be circumcised. 鈥淭he particular young man
who told me about it was doing it mainly because he thought it was time he got
himself a girlfriend,鈥� says Mundhenk. Though circumcision is not part of the
local culture, men in Papua New Guinea now believe it prevents diseases such as
AIDS.
But does it? Epidemiologists are arguing over whether circumcision really
does reduce the transmission of HIV and, if so, what should be done about it.
Public health officials are desperate for anything that could slow the spread of
the virus. Nearly a million people in North America and half a million in
Western Europe live with HIV, and in sub-Saharan Africa more than 22 million
people are HIV-positive.
Next week, scientists at the first major AIDS conference ever held on African
soil, the 13th International AIDS Conference in Durban, South Africa, will
explore why Africa bears such a terrible burden of disease. Some researchers
believe that Africans鈥� immune systems might be more susceptible to the virus, or
that the subtypes of HIV prevalent in Africa spread more rapidly. But other
epidemiologists point to the fact that most African men are not circumcised.
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Circumcision has long been an ignored risk factor, says Robert Bailey of the
University of Illinois at Chicago. Last November, Bailey and Daniel Halperin of
the University of California San Francisco wrote an article for The
Lancet in which they pointed to evidence that circumcision protects against
HIV, and accused public health agencies of disregarding it. Further studies
since then have added weight to their position. 鈥淭he tide has started to turn
just in the last three months,鈥� says Bailey, noting that the Durban conference
has a special session on circumcision.
But growing interest doesn鈥檛 mean universal acceptance. Though the HIV
epidemic in Africa is horrifying, no one has proof that widespread circumcision
would reduce the virus鈥檚 spread. Ronald Gray of the Johns Hopkins School of
Public 午夜福利1000集合 in Baltimore, thinks they鈥檙e grasping at straws.
Experts have long considered the role the foreskin might play in HIV
infection. Its inner surface is a mucous area with cells that contain a receptor
exploited by HIV. Tears and abrasions in the foreskin may ease the entry of the
virus. And men with foreskins have a higher incidence of ulcerative sexually
transmitted diseases, which also provide an open door for the virus.
But establishing an epidemiological link between circumcision and HIV is
complicated by cultural factors. Muslim men, for example, are usually
circumcised, but they also have other behaviour that reduces their risk of HIV.
Sex outside marriage, for example, is strictly discouraged. But some places with
a high rate of circumcision, such as Ethiopia, still have an HIV epidemic, so it
can鈥檛 be the only factor.
On the other hand, many studies do show a clear link between circumcision and
the spread of HIV. A few years ago, epidemiologists compared four African cities
with different rates of HIV. They found that a town in Benin and one in
Cameroon鈥攚here the majority of men were circumcised鈥攈ad lower HIV
rates than towns in Kenya and Zimbabwe, where fewer than a third of men were
circumcised.
This result convinced Richard Hays of the London School of Hygiene and
Tropical Medicine to carry out a fresh analysis of 27 published studies of HIV
transmission among heterosexuals in Africa. He rejected 12 of them, because of
doubts over whether they were properly controlled for cultural differences, but
the remaining 15 all showed that circumcision did protect. 鈥淭he prevalence was
two-and-a-half times higher in uncircumcised men,鈥� he says. Once a sceptic, Hays
has changed sides. 鈥淲e can鈥檛 ignore this data,鈥� he says.
Further compelling information comes from studies of couples where only one
partner has HIV. Gray and his colleagues looked at 187 couples where the woman
had HIV. They found that none of the 50 circumcised HIV-negative men contracted
HIV from their partner, while 40 of the 137 uncircumcised men did (The New
England Journal of Medicine, vol 342, p 921). These ethically dubious
studies caused a storm when it was revealed that the infected people didn鈥檛 get
treatment for HIV and their partners were not informed of their infections.
In Durban, Gray will also report on a study of 228 couples where the man had
HIV. He found that circumcised men were very unlikely to transmit HIV to their
female partners. But he says that only a randomised trial can show whether
circumcision really can reduce the incidence of HIV.
Others, like Bailey, say the evidence demands action now. For six months, he
has been running a trial in Western Kenya鈥檚 Nyanza province that involves
teaching doctors at government clinics about circumcision and giving them
supplies for 1000 operations. 鈥淲e want to see if circumcision is acceptable, and
if setting up the services and information is feasible,鈥� says Bailey, who has
done surveys showing that many cultures that don鈥檛 traditionally circumcise
would be willing to try it.
For now, international health organisations are watching and waiting. UNAIDS,
the Joint UN Programme on HIV/AIDS, 鈥渨ill not make a policy statement before
some quite important operational issues are solved鈥�, says Michel Cara毛l of
the UNAIDS office in Geneva. The WHO is also cautious. 鈥淲e鈥檙e keeping an eye on
the evidence and we鈥檙e keeping an open mind,鈥� says Timothy Farley, who works on
clinical trials for the WHO. 鈥淭he WHO is not on the verge of issuing any policy
statement on this.鈥�
Promoting circumcision has problems. Men may choose to be circumcised in the
belief that this will make them safe from HIV, and consequently engage in more
risky sexual behaviour. Another difficulty is ensuring hygienic operations.
There are thorny ethical issues too. 鈥淵ou don鈥檛 need to circumcise a baby boy to
keep him from getting AIDS,鈥� says Margaret Somerville, director of the Centre
for Medicine, Ethics and Law at McGill University in Quebec.
In developed nations, opinion in recent years has swung against circumcising
boys because of concerns about mutilating children without their consent.
鈥淧eople get mixed up between there being a medical benefit and a medical
justification. There can be a medical benefit to getting your leg amputated.
You鈥檙e not going to have sore toes,鈥� says Somerville. She argues that
circumcision should only be done on people old enough to give consent. 鈥淲hat if
we tested baby girls for the breast cancer gene and said let鈥檚 remove their
breast tissue? Would we feel it was right to do that to those baby girls? I
don鈥檛 think so.鈥�
But Edward Green, a medical anthropologist based in Washington DC, says that
traditional healers already promote circumcision as a way of staving off AIDS.
He wants a clear public health message that while circumcision isn鈥檛 a panacea,
men who want it should go to hospital. 鈥淚f we continue to be silent on this,
that can鈥檛 help the situation.鈥�