During 2012, 3250 gay men were diagnosed with HIV in the United Kingdom, the
largest number of cases ever recorded in this group. While there are several
indications that more gay men are getting tested (and so some of the diagnoses
are of previously acquired infections), the figures are also fuelled by risky
behaviour and new infections. Epidemiologists at Public Health England estimate
that around 2400 men who have sex with men (MSM) newly acquired HIV during the year – a
figure that has not changed in the past decade.
Whereas the annual number of diagnoses in gay men and other
men who have sex with men has hovered between 2800 and 3000 cases in recent
years, 3250 men were diagnosed in 2012, accounting for half of all new
diagnoses. The median age at diagnosis was 34, although one in nine was over 50
Several pieces of data suggest that efforts to increase the
number of gay men who test, and the frequency with which they do so, are beginning
to pay off:
- The proportion of gay men living with HIV who were
unaware of their infection fell from 26% in 2010 to 18% in 2012. The estimated
number of gay men with undiagnosed infection was 10,300 men in 2010 and 7300
men in 2012.
- The proportion of new diagnoses that were made
late (with a CD4 cell count below 350 cells/mm3) dropped from 38% in
2010 to 34% in 2012, although the absolute number has not gone down.
- The number of gay male attendees of sexual
health clinics taking an HIV test increased by 13% in one year, from 64,270 in
2011 to 72,710 in 2012. (Unfortunately, equivalent figures are not available
for testing in other settings.)
Improved HIV testing practices have therefore likely
contributed to the greater number of HIV infections which are diagnosed. But
Public Health England also believe that HIV transmission continues at high
levels – their estimations of HIV incidence using
a back-calculation analysis suggest that there have been 2300 to 2500 new
infections in gay men each year over the past decade. The large majority of transmissions
originate in men unaware of their own infection.
Data from the Recent Infection Testing Algorithm (RITA)
point to ongoing HIV transmissions. One-in-five newly diagnosed gay men are
thought to have acquired their infection in the previous six months, with the
proportion highest in younger men and in Londoners.
In several other places, the new epidemiological report
points to the particular role that London plays in the UK’s epidemic,
especially among gay men – far more gay male diagnoses were made in the city
(1450) than in other regions, with the upward trend in diagnoses most marked
there. The number of tests in sexual health clinics also rose faster in London
than in the rest of the country.
Moreover, half of the UK’s local authorities which have a
high prevalence of HIV (across all population groups) are located in London. Havering,
on the eastern outskirts of the city, is the only London borough with an HIV
prevalence below 2 per 1000 people aged 15-59 years.
Nonetheless, there is an uneven geographical spread of HIV
within London, with particular concentrations in areas with more socioeconomic
problems. In the most deprived areas (defined with reference to a range of
economic, social and housing indicators), 7 in 1000 people had diagnosed HIV.
In the least deprived areas, 2.4 in 1000 had HIV.