Sexual behaviours, HIV testing, and the proportion of men at risk of transmitting and acquiring HIV in London, UK, 2000–13: a serial cross-sectional study

Abstract

5Background: HIV incidence among men who have sex with men (MSM) in the UK has remained unchanged 6 over the last decade despite increases in HIV testing and antiretroviral (ARV) coverage. Here we examine 7 trends in sexual behaviours and HIV testing among MSM, and explore risk of transmitting and acquiring 8 HIV. 9Methods: Ten cross-sectional surveys between 2000 and 2013 using self-administered questionnaires and 10 oral HIV antibody testing among MSM in London gay social venues. 11 12 Findings: Of 11,876 MSM recruited, 12.7% (n=1512) were HIV positive with no significant trend over time. Over the study period, the proportion reporting unprotected anal intercourse (UAI) during the previous 19 year increased from 43.2% (513/1187) to 52.6% (394/749) (p<0.001) and serosorting (exclusively) 20 increased from 18.3% (207/1132) to 27.7% (177/6369) (p<0.001). Overall, one in 43 (2.3%, 268/11570) 21 had undiagnosed infection and reported UAI and were therefore at risk of transmitting HIV. A further one 22 in 45 (2.2%, 259/11570) had diagnosed infection and reported UAI and not exclusively serosorting in the 23 previous year. Whilst we did not collect data on ARV or viral load, surveillance data suggest that a small 24 proportion of the latter group will have detectable viral load and hence be at risk of transmitting HIV. One 25 in four HIV negative men (25.4%, 2633/10364) were at higher risk of acquiring HIV (defined as HIV 26 negative MSM either reporting ≥1 casual UAI partner(s) in the previous year or not exclusively 27 serosorting). The proportions of men at risk of transmission or acquisition changed little over time. 28Undiagnosed men reporting UAI and diagnosed men not exclusively serosorting had consistently higher 29 partner numbers than other MSM over the period. 30 31 Interpretation: Undiagnosed HIV may be increasingly recently acquired infection, during which persons 32 are most infectious. This coupled with the high partner numbers of a core group of MSM at risk of 33 transmitting HIV, and the lack of decline in the proportion of men at higher risk of acquiring the infection, 34 may explain the sustained HIV incidence. One of these studies uses a back-calculation approach based on CD4 cell count at diagnosis 3 ; 45 the second is a dynamic model of sexual behaviours 4 . Given the greatly increased uptake of HIV testing 46 and antiretroviral (ARV) treatment in the last decade, which, by reducing viral load should reduce 47 transmission, the sustained level of HIV incidence supports the notion that risk behaviours must have 48 increased over this period. 5;6 Studies suggest, since the introduction of ARVs in the mid 1990's, the 49 prevalence of high risk sexual behaviours among MSM is increasing (at least partly) due to 'treatment 50 optimism', relating both to the dramatically reduced morbidity and mortality associated with the 51 infection, and the reduced risk of transmission from a positive partner (the latter discovered in later 52 years). 7-10 Few behavioural studies are able to explore trends ...

Impact and Cost-effectiveness of Selective Human Papillomavirus Vaccination of Men Who Have Sex With Men

“…MSM attending GUM clinics are at higher risk of human immunodeficiency virus (HIV) infection and sexually transmitted infection (STI) [11, 12]. Antiretroviral treatment coverage is high (90%) for the 38432 MSM accessing HIV care [13].…”

Declining prevalence of undiagnosed HIV in Melbourne: results from community‐based bio‐behavioural studies of gay and bisexual men

“…Findings from cross‐sectional studies of GBM in Glasgow and Edinburgh (2005–2011) show that, despite significant increases in HIV testing in the past 12 months, undiagnosed HIV prevalence remained relatively stable and that nearly half of undiagnosed GBM in 2011 reported testing for HIV within the past 12 months 13 . Similarly, cross‐sectional studies of venue‐recruited GBM in London (2000–2013) showed significant increases in past 12 months HIV testing among men with undiagnosed HIV infection (29% to 67%) 14 . When considered alongside modelling of jurisdiction‐specific HIV epidemics suggesting that most of HIV transmissions among GBM are attributed to undiagnosed acute infections, 6,38 these findings support calls for novel strategies to improve HIV testing accessibility to facilitate high frequency testing 13,23,39,40 .…”

“…13 Similarly, cross-sectional studies of venue-recruited GBM in London (2000-2013) showed significant increases in past 12 months HIV testing among men with undiagnosed HIV infection (29% to 67%). 14 When considered alongside modelling of jurisdiction-specific HIV epidemics suggesting that most of HIV transmissions among GBM are attributed to undiagnosed acute infections, 6,38 these findings support calls for novel strategies to improve HIV testing accessibility to facilitate high frequency testing. 13,23,39,40 One such strategy is to make prevention interventions like HIV pre-exposure prophylaxis more accessible to motivate GBM who have high risk condomless sex to come forward for testing.…”

“…Bio‐behavioral surveys of GBM in the UK have shown discrepant findings. Persistent levels of undiagnosed HIV (26.3%–25.4%) were found in Glasgow and Edinburgh between 2008 and 2011, 13 while declines in undiagnosed HIV from 34% to 24% were detected in venue‐recruited MSM in London between 2000 and 2013 14 . Surveillance of undiagnosed HIV allows for the evaluation of local HIV prevention strategies that focus on promoting HIV testing and treatment, the refinement of HIV transmission models and can help guide targeted HIV prevention strategies.…”

What are the characteristics of, and clinical outcomes in men who have sex with men prescribed HIV postexposure prophylaxis following sexual exposure (PEPSE) at sexual health clinics in England?

“…Furthermore, national trends show a steadily increasing number of HIV diagnoses in MSM, and evidence from community-based surveys of sexual behaviour in MSM suggest that there is a need to enhance the existing HIV prevention package. Community-based surveys have shown increases in UAI with casual partners,16 17 self-reported STIs16 and UAI with a main partner of a different HIV status 18…”