Uncircumcised men are nearly seven times more likely to become HIV positive, giving further support to findings that circumcision offers some protection against the virus, according to a study published today.

The study by Robert Bollinger and colleagues from Johns Hopkins University Medical School in Baltimore, US and the National Aids Research Institute in Pune, India, was published as a тАЬresearch letterтА? in The Lancet medical journal.

тАЬIt is now about the ninth study which followed men who are HIV-negative over a period of months or years. It is the ninth study in a row which has found that the effect (of circumcision) is significant,тА? said Robert Bailey, Professor of epidemiology and biostatistics at the University of Illinois at Chicago, who was not connected with BollingerтАЩs study.

тАЬThe fact that they found no behavioural differences between the two groups is all the more compelling, and indicates that there is a biological factor,тА? Prof Bailey said.

Prof Bailey, like the authors of the Lancet study, believes cells in the foreskin may be particularly susceptible to infection.

The association between circumcision and a reduced risk of HIV was noted as early as 1987, when Dr William Cameron of the University of Manitoba in Canada reported findings from a study in Kenya.

The research published in The Lancet tracked 2,298 men who were being treated at three clinics in Pune, and who were confirmed to be HIV-negative at the start of the study.

The study also found that circumcised men were as much at risk of gonorrhoea, herpes simplex and syphilis as the uncircumcised.

The nine studies have all tried to control for variables in behaviour, Prof Bailey said. тАЬA randomised control trial is what is necessary now to really nail this down,тА? he said.

Circumcision Protects Against Aids - Study