Researchers in London are conducting a study to establish whether MSM who cruise on Internet chatrooms are more tempted to participate in riskier sexual behaviour as compared to cruising in gay bars and gyms, reports the The (UK) Guardian.

The UK Department of Health and the medical research council has commissioned researchers from the Institute of Health Sciences, City University, London to determine whether the internet is a factor in making men take greater risks than they would through gay bars and clubs.

The two-year study will involve 2,500 MSM men in London.

The government hopes to reduce new HIV cases by 25% while health officials and charities campaigning on Aids and HIV issues are concerned that people are turning a deaf ear to "safe sex" messages and awareness campaigns.

Professor Jonathan Elford, who is leading the study group, said (of chat-rooms): "These increased opportunities for having sex may have been matched by a corresponding rise in high risk sexual activity. Consequently we may need to find new ways of getting safe sex messages to gay men."

"For example, we could see an increase in HIV infections in regions which currently report low HIV prevalence because of the boundless reach of the Internet as a meeting place."

Nick Partridge, chief executive of the Terrence Higgins Trust's said research would "help us better understand the changing patterns of gay men's sex lives and ensure that HIV prevention campaigns continue to be relevant and effective".

Of the some 23,000 people in Britain who have been diagnosed as having HIV, about half are gay men, and two thirds of that number is living in London.