Study: HIV most often passed on by younger gay men who have not been diagnosed

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A study shows the vast majority of HIV infections for gay men in Britain occur in men with undiagnosed HIV who are under 35.

AIDSmap reports a modelling study based on the UK’s HIV epidemic among men who sex with men (MSM) found that two-thirds of infections originate in MSM with undiagnosed HIV, 85% in MSM who are not taking treatment and 90% within the context of an ongoing sexual partnership.

The study shows HIV transmissions most frequently involve MSM under the age of 35 who report relatively high levels of sexual activity (at least two new sexual partners each year).

“The majority of new HIV infections among MSM in the United Kingdom during 2001-2020 is expected to be accounted for by a small group of highly sexually active individuals under the age of 35 years, living with undiagnosed HIV in the asymptomatic stage,” the authors concluded.

Figures released last month from Public Health England (PHE) showed 3,250 gay and bisexual men were diagnosed with HIV last year – the highest ever figure.

One in eight gay and bisexual men in London is HIV positive.

It is estimated that over 7,000 gay men have an HIV infection that remains undiagnosed and that an estimated 2,800 men acquired HIV in 2013.

PHE said the figures underline the need to further increase both the numbers and frequency of HIV tests, which is critical to tackling the ongoing high levels of HIV transmission.