The Department of Health (DoH) has launched a research programme to find out whether the web may be responsible for an increase in high-risk sexual activity among gay and bisexual men.
Ministers, officials and Aids and HIV charities are concerned that 'safe sex' messages are losing their impact as a result of the internet.
Researchers, led by Jonathan Elford of the Institute of Health Sciences at City University, London, have been asked by the DoH and the Medical Research Council to establish whether the internet is a factor in men taking greater risks than they would normally.
More than 2,500 gay and bisexual men in London will be involved in the two-year study.
Researchers are concerned that they could see an increase in HIV infections in areas where there is a low HIV incidence because the internet offers the opportunity to meet more people.
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