Foreskin cells are thought to be more vulnerable to HIV infection.
Male circumcision ‘could significantly reduce‘ the burden of HIV, a study suggested earlier in 2005. Now as of 13 December 2006, Experts say circumcision ‘can cut‘ the rate of HIV infection in heterosexual men by 50%, results from two African trials show.
It concluded that the operation could avert about six million HIV infections and three million deaths in sub-Saharan Africa over the next 20 years.
The findings build on research, published in 2005, that suggested circumcision reduced HIV infection risk in heterosexual men by about 60%.
The research is published in the journal PLoS Medicine.
An international team of researchers used data on HIV infection rates and the prevalence of male circumcision across Africa to predict the potential impact.
Using mathematical modelling, they looked at what would happen if, over the next 10 years, all men in sub-Saharan Africa were circumcised.
They calculated that within a decade some two million new HIV infections and 300,000 deaths could be prevented. And in the ten years after that, a further 3.7 million infections and 2.7 million deaths could be avoided – with one in four of the deaths prevented being in South Africa.
The findings are so striking, the US National Institutes of Health decided it would be unethical to continue and stopped the trials early.
The two trials of around 8,000 men took place in Uganda and Kenya were due to finish in July and September 2007 respectively.
But after an interim review of the data by the NIH Data and Safety Monitoring Board, it was decided to halt the trials as it was unethical not to offer circumcision in the men who were acting as controls.
Bleeding less likely
The trial in Kenya found a 53% reduction in new HIV infections in heterosexual men who were circumcised while the Ugandan study reported a drop of 48%.
Results last year from a study in 3,280 heterosexual men in South Africa, which was also stopped early, showed a 60% drop in the incidence of new infections in men who had been circumcised.
There are several reasons why circumcision may protect against HIV infection.
Specific cells in the foreskin may be potential targets for HIV infection and also the skin under the foreskin becomes less sensitive and is less likely to bleed reducing risk of infection following circumcision.
When Aids first began to emerge in Africa, researchers noted that men who were circumcised seemed to be less at risk of infection but it was unclear whether this was due to differences in sexual behaviour.
A modelling study done by international Aids experts earlier this year showed that male circumcision could avert about six million HIV infections and three million deaths in sub-Saharan Africa.
A further trial in Uganda to assess the risk of HIV transmission to female partners is due to report in 2008 but the effect among men who have sex with men has not yet been studied.
Social factors & Implementation
Catherine Hankins, chief scientific adviser to the United Nations Programme on HIV/Aids (UNAIDS) and a co-author on the study, said: “The big message from the paper is that there is a tremendous potential for male circumcision to have an effect on the HIV epidemic, particularly in sub-Saharan Africa.
Currently, she said, circumcision in sub-Saharan Africa varied greatly per country: “In west and central Africa have high circumcision rates and lower HIV rates. Southern and eastern Africa have lower circumcision rates and higher HIV rates.”
Dr Kevin De Cock, director of the HIV/Aids department of the World Health Organization told the BBC the results were a “significant scientific advance” but were not a magic bullet and would never replace existing prevention strategies.
“We will have to convene a meeting which we hope will happen quite soon to review the data in more detail and have discussions about the implications.
“This is an intervention that must be embedded with all the other interventions and precautions we have. Men must not consider themselves protected. It’s a very important intervention to add to our prevention armamentarium.”
NIH director Dr Elias Zerhouni said: “Male circumcision performed safely in a medical environment complements other HIV prevention strategies and could lessen the burden of HIV/Aids, especially in countries in sub-Saharan Africa where, according to the 2006 estimates from UNAids, 2.8 million new infections occurred in a single year.”
Dr Jeckoniah Ndinya-Achola, co-principal investigator at the University of Nairobi, Kenya said: “The Ministry of Health of the Kenyan government is already holding discussions about how this can be made available. It will need a certain amount of improvement to existing facilities.”
Deborah Jack, chief executive of the National AIDS Trust, said: “These findings are encouraging and it is clear the promotion of voluntary circumcision can play an important role in reducing the risk of HIV transmission, as part of a comprehensive prevention programme.
“However, people who are circumcised can still be infected with HIV and any awareness campaign would have to be extremely careful not to suggest that it protects against HIV or is an alternative to using condoms.”
[courtesy of journal PLoS Medicine, BBC news, etc.]