HIV incidence in men who have sex with men in England and Wales 2001–10: a nationwide population study

Abstract

SummaryBackgroundControl of HIV transmission could be achievable through an expansion of HIV testing of at-risk populations together with ready access and adherence to antiretroviral therapy. To examine whether increases in testing rates and antiretroviral therapy coverage correspond to the control of HIV transmission, we estimated HIV incidence in men who have sex with men (MSM) in England and Wales since 2001.MethodsA CD4-staged back-calculation model of HIV incidence was used to disentangle the competing contributions of time-varying rates of diagnosis and HIV incidence to observed HIV diagnoses. Estimated trends in time to diagnosis, incidence, and undiagnosed infection in MSM were interpreted against a backdrop of increased HIV testing rates and antiretroviral-therapy coverage over the period 2001–10.FindingsThe observed 3·7 fold expansion in HIV testing in MSM was mirrored by a decline in the estimated mean time-to-diagnosis interval from 4·0 years (95% credible interval [CrI] 3·8–4·2) in 2001 to 3·2 years (2·6–3·8) by the end of 2010. However, neither HIV incidence (2300–2500 annual infections) nor the number of undiagnosed HIV infections (7370, 95% CrI 6990–7800, in 2001, and 7690, 5460–10 580, in 2010) changed throughout the decade, despite an increase in antiretroviral uptake from 69% in 2001 to 80% in 2010.InterpretationCD4 cell counts at HIV diagnosis are fundamental to the production of robust estimates of incidence based on HIV diagnosis data. Improved frequency and targeting of HIV testing, as well as the introduction of ART at higher CD4 counts than is currently recommended, could begin a decline in HIV transmission among MSM in England and Wales.FundingUK Medical Research Council, UK Health Protection Agency.

Implications for a policy of initiating antiretroviral therapy in people diagnosed with human immunodeficiency virus: the CAPRA research programme

“…2 Antiretroviral therapy (ART) is now highly successful in reversing the effects of HIV and has led to death rates in successfully treated people that are not much greater than those of the general population. 3,4 Given that there are reductions in infectivity of people on ART, 5 there is widespread interest in the potential effect of ART in controlling the HIV epidemic, 6 but there are a number of areas, including the UK, in which ART use is high among MSM, and yet incidence has not declined [7][8][9][10] and its potential impact in epidemics in MSM has been questioned. 9,11 In the Comprehensive Assessment of the Prevention Role of Antiretroviral therapy (CAPRA) programme of research that started in 2010 we set out to address what would be the population-level clinical effectiveness, and cost-effectiveness, of introduction of a policy of initiating ART in all people with a diagnosed HIV infection.…”

Australian sexually transmissible infection and HIV testing guidelines for asymptomatic men who have sex with men 2014: a review of the evidence

“…[133][134][135][136][137][138] In Australia, an estimated 12-33% of HIV among MSM remains undiagnosed. 139,140 Despite around two-thirds of gaycommunity-attached MSM consistently reporting testing, 141 less than 40% of high-risk MSM return for HIV testing within 1 year of a previous test.…”

Results from a Method for Estimating HIV Incidence Based on the First Cd4 Count among Treatment-Naïve Cases: Brazil, 2004-2013

“…To ensure effective implementation of prompt access to treatment and other prevention interventions, it is essential to have estimates of HIV incidence for describing the current dynamics of the epidemic [2,3]. Trends in HIV incidence indicate the degree to which HIV transmission is controlled [4], which groups are most at risk for HIV infection and help to identify the emergence of new sub-epidemics in the general population [5].…”

“…More recently, updates of back-calculation models relying on new HIV diagnoses have been applied for HIV incidence estimation [11][12][13][14][15]. One of the difficulties faced is to distinguish the contribution of changes in testing patterns in the trends of HIV reported cases [4].…”

“…Lately, methods based on the first CD4 count after HIV diagnosis have been developed to estimate HIV incidence in United Kingdom [4,15], France [11], Brazil [12] and United States [13,14]. The main assumption of these models is that among antiretroviral therapy (ART)-naïve individuals, CD4 cell counts decrease over time [30] and the time since infection can be ascertained by applying an estimated rate of CD4 count decline [31].…”