9 May, 16 | by Leslie Goode, Blogmaster
The potential role of frequent HIV testing in curbing the HIV epidemic among the MSM population has long been recognized. The introduction of the strategy of ‘opt-out’ testing in the UK (2007), as in other countries at around the same time, brought a steep rise in testing, followed by stabilization (McDaid & Hart (STIs); Saxton & Hughes (STIs) (for New Zealand); Heijman & Prins (STIs) (Netherlands)), and may now ‘have reached its limit in maximizing routine uptake’ (McDaid & Flowers). Nonetheless, amongst UK MSM at least, HIV incidence is not declining. UK guidelines currently recommend annual HIV testing for MSM, and three-monthly testing for those ‘at higher risk’. But how far are these goals being met? An audit conducted in UK GUM clinics (Desai & Suillivan/STIs) was reassuring; but a recent (2013) cross-sectional survey of gay bars in Glasgow reports levels of HIV testing over the previous six months of only 37%, and a relatively high proportion of ‘high-risk’ takers figuring among those who had never tested (OR: 0.51)( McDaid & Flowers (STIs)).
Last month saw the publication of study (McDaid & Flowers (M&F)) based on data from three cross-sectional surveys – Glasgow/Edinburgh gay commercial venues; an internet-based Scotland-wide survey; London gay social venues – and including 2409 MSM in total. Frequency of testing was reckoned over a two-year period, and classified as ‘one or less’, ‘two or three times’, or ‘four or more times’. On this basis, the study estimates the proportion testing annually at only 54.9% – and the proportion of those reporting higher risk unprotected anal intercourse (UAI) (=37.8% of the total) who tested four or more times at only 26.7%. So neither in respect to MSM in general, nor in respect to those ‘at high risk’ are the UK national guidelines being met. Moreover, involvement in higher risk UAI – unlike number of sexual partners and AI partners – turns out not to be significantly correlated with the highest rates of testing; while more of those reporting higher risk activities claimed to have tested as a result of a perceived risk event, rather than as part of a regular check-up. The authors conjecture the episodes of higher risk UAI may have been less frequent events (albeit reported by a third of participants) after which the participants, being risk-aware, took appropriate preventative action. This seems a plausible interpretation.
Studies of HIV testing in other countries published in STI Journal seem to show a broadly comparable situation, with testing levels for MSM and high-risk MSM consistently falling short of respective national guidelines. Thus Saxton & Hughes (STIs) in location based surveys in Auckland report levels of MSM annual testing rising slowly to 50% in 2011; while Guy & Hellard (STIs) surveying testing in Australian GP clinics give figures for annual testing by MSM, and high-risk MSM, of 35% and 15% respectively as of 2010. As for the US, Katz & Stekler (STIs) report levels of annual testing of 77%, but, as the location of this survey was GP clinics, an appropriate UK comparator would be the study reported by Desai & Suillivan/STIs, which reports levels of 92%.
In their recommendations M&F stress the importance of reducing the known barriers to HIV testing, and also draw our attention to the key role that testing will have in facilitating the effectiveness of future PrEP interventions, given the need for participants in PrEP to have an accurate knowledge of their HIV status.