/ 6 September 2005

Increased safety at a snip

Mobile ”chop shops” may be one of the best ways to curb South Africa’s HIV/Aids epidemic, according to a major study carried out in Orange Farm, near Johannesburg. Not an outfit that dismembers cars, but one offering a more intimate service — circumcision.

Circumcising men appears to reduce their chances of catching HIV by up to 65% — a far higher level of protection than scientists would consider the minimum requirement for a successful vaccine. So dramatic was the protective effect that the trial was stopped early because it was considered unethical not to offer the uncircumcised men in the control group the chance to have the operation immediately.

The two-year study was carried out by a team of French and South African researchers, led by Dr Bertrain Auvert of the French National Institute for medical research and Dr Adrian Puren of the South African National Institute of Communicable Diseases, who headed the local team.

More than 30 studies around the world have suggested that circumcision can protect men from HIV to some degree, but this is the first time a randomised controlled study has been done.

The results of the Orange Farm trial have led to calls for safe male circumcision to be integrated into national HIV-prevention strategies — especially as more traditional prevention efforts have not been particularly successful.

As part of the study, more than 3 200 HIV-negative men aged between 18 and 24 agreed to be circumcised. In an area where just under one in three adults is thought to be HIV-positive, more than 70% of men surveyed said they would be circumcised if it reduced their chances of becoming infected. Already, one in five men in the area had undergone the operation at the relatively late average age of 17.

The trial was divided into two: 1 582 men were circumcised immediately, and the remainder were scheduled to undergo the operation 21 months later. However, the trial was stopped nine months early because of the ethical concerns over the dramatic contrast in the number of new infections of the circumcised men, and those who had not yet had the chop.

Only 15 of the circumcised men contracted HIV during the first 21 months of the study, while three times as many uncircumcised men in the control group became infected. These results suggested that between six and seven of every 10 subjects in the initially circumcised group avoided becoming infected with HIV as a result of the operation.

The circumcisions were carried out by doctors under local anaesthetic, without serious mishaps. About 31% of men said they felt pain, while 15% said they had problems dealing with the new appearance of their penis.

Men who are not yet circumcised have a microclimate under their foreskin that allows more bacterial and fungus growth. Failure to wash regularly increases the chances of infections. Also, the risk of infection is heightened by -minute tears to the foreskin during sex, especially if the man’s sexual partner is not properly lubricated — for example during ”dry sex”, or anal sex.

The Orange Farm results, combined with similar results from different studies, have led to calls for mass circumcision to be considered as a means of containing the spread of the epidemic. Pressure for such a move will intensify if the randomised controlled studies being carried out in other African countries show the same effect.

However, the problem with incomplete protection is that it can result in what doctors delicately call ”behavioural disinhibition” — if people think they are protected, they take more risks. In San Francisco the success of anti-retroviral drugs has led to increased risk-taking and higher levels of infection.

As one public health specialist put it: ”You still need to use a condom. Otherwise it would be like playing Russian roulette, but with 12 chambers instead of six.”