Number of gay men catching HIV has doubled in 20 years because new drugs have 'encouraged unsafe sex'
Between 1990 and 2010 there was a 26 per cent increase in the number of men having unprotected sexCases of HIV rose by 76 per cent in this period
Experts say introduction of effective drugs is to blame
23:01 GMT, 15 February 2013
01:31 GMT, 16 February 2013
The number of gay men catching HIV has almost doubled in 20 years because new drugs have encouraged unsafe sex, new research shows.
Between 1990 and 2010, cases rose by 76 per cent due to fewer people using condoms. Experts say this is due to the introduction of antiretroviral drugs that are effective in treating the disease.
During this time there was a 26 per cent increase in the proportion having unprotected sex, according to the study.
The number of gay men catching HIV has almost doubled in 20 years because new drugs have encouraged unsafe sex
Professor Andrew Phillips, of University College London, said: 'We created a model reconstructing the HIV epidemic in men who have sex with men in the UK.
'In doing so, we were able to explore the interplay between HIV testing rates, antiretroviral (ART) treatment and sexual behaviour on HIV transmission and incidence.
'By better understanding the driving forces behind the trends we have seen in the past, it will allow us to make informed choices to reduce new HIV infections in the future.'
But the findings, published in the journal PLOS ONE, suggest the increase in infections would have been 68 per cent greater without the introduction of ART in the same period, and 400 per cent more if condom use among men who have sex with other men had ceased entirely from the year 2000 onwards.
Dr Valerie Delpech, head of HIV
surveillance at the Health Protection Agency, said: 'Our research
provides important evidence to support current UK public health
recommendations on expanded HIV testing and higher levels of ART
coverage, to reduce new infections among men who have sex with men.
But the findings also suggest infections would have been 68 per cent greater without the introduction of antiretroval drugs
'However, we see it is also vital condom use education continues as not only does this have a strong limiting effect on the HIV epidemic, but only a modest increase in unprotected sex is enough to erode the benefits of other interventions.'
Exploring other scenarios, the research found cases would have reduced by 25 per cent if HIV testing levels had been higher, by 32 per cent if ART had been prescribed at diagnosis or by 62 per cent if both interventions had been combined.
Effective ART therapy reduces how infectious peple with HIV are, lowering the risk of transmission.
Dr Delpech added: 'Everyone should use a condom when having sex with new or casual partners, until all partners have had a sexual health screen.
'We also encourage men who have sex with men to get an HIV and STI screen at least annually, and every three months if having condomless sex with new or casual partners – and clinicians to take every opportunity to recommend HIV testing to this group.
'Through combining earlier and more frequent HIV testing, programmes that reduce unsafe sexual behaviour and higher levels of ART coverage for those requiring it, we could substantially reduce HIV transmission in this group.'