ObjectivesIn the UK, free HIV care is provided through dedicated HIV clinics. Using the national cohort of men who have sex with men (MSM) with diagnosed HIV infection and estimates of the number of undiagnosed men, we assessed whether high retention in HIV care and treatment coverage is sufficient to reduce HIV transmission.
MethodsAntiretroviral therapy (ART) uptake and viral load distribution among diagnosed men were analysed by treatment status and CD4 count for the period between 2006 and 2010. A multiparameter evidence synthesis (MPES) method was used to estimate the size of the undiagnosed population. The viral load distribution among newly diagnosed untreated men was applied to the undiagnosed population. Infectivity was defined as a viral load > 1500 HIV-1 RNA copies/mL.
ResultsBetween 2006 and 2010, ART coverage among all HIV-infected MSM (diagnosed and undiagnosed) increased from 49 to 60%, while the proportion of infectious men fell from 47 to 35%. Over the same period, the number of all HIV-infected MSM increased from 30 000 to 40 100 and the number of infectious MSM remained stable at 14 000. Of the 14 000 infectious MSM in 2010, 62% were undiagnosed, 33% were diagnosed but untreated, and 5% received ART. Extending ART to all diagnosed HIV-infected MSM with CD4 counts < 500 cells/mL in 2010 would have reduced the overall proportion of infectious men from 35 to 29% and halving the proportion who were undiagnosed would further have reduced this to 21%.
ConclusionsHigh ART coverage in the UK has reduced the infectivity of the HIV-diagnosed population. However, the effectiveness of treatment as prevention will be limited unless the undiagnosed population is reduced through frequent HIV testing and consistent condom use.
IntroductionThe demonstration that prevention of HIV transmission was possible through antiretroviral therapy (ART) was described as 'a defining moment for HIV control' in mid-2011 [1] and the 'breakthrough of the year' for scientific research in December 2011 [2]. ART has been shown to be highly efficacious at preventing transmission from HIVinfected to HIV-negative heterosexual partners, providing that the HIV-positive partner adheres to treatment so that their viral load becomes undetectable [3].While the benefit of HIV treatment for HIV-negative heterosexuals in HIV-serodiscordant relationships has been demonstrated, there is uncertainty surrounding the clinical benefits of 'early' ART (starting ART before the CD4 count reaches 500 cells/mL) for HIV-positive individuals.
ORIGINAL RESEARCH 563The START trial [4] is designed to identify the impact of early ART initiation among the HIV-diagnosed population on the development of AIDS-related and non-AIDS-related illnesses. Additional measurable outcomes include adherence, the development of antiretroviral resistance and patient satisfaction. This work will directly inform future national and international treatment policies. However, even if early treatment for the diagnosed HIVpositive population is found to be clinically beneficial,...