Combination prevention and HIV: a cross-sectional community survey of gay and bisexual men in London, October to December 2016

Background: Men who have sex with men (MSM) are at risk of HIV and are an important population to monitor and ameliorate combination prevention efforts. Aim: To estimate HIV prevalence and identify factors associated with frequent HIV testing (= 2 HIV tests in the last year) and pre-exposure prophylaxis (PrEP) use among MSM in London. Methods: For this cross-sectional study, MSM recruited from 22 social venues provided oral-fluid samples for anonymous HIV antibody (Ab) testing and completed a questionnaire. Factors associated with frequent HIV testing and PrEP use were identified through logistic regression. Results: Of 767 men recruited, 545 provided an eligible oral specimen. Among these, 38 MSM (7.0%) were anti-HIV positive including five (13.2%; 5/38) who reported their status as negative. Condomless anal sex within the previous 3 months was reported by 60.1% (412/685) men. Frequent HIV testing was associated with, in the past year, a reported sexually transmitted infection (adjusted odds ratio (AOR): 5.05; 95% confidence interval (CI): 2.66-9.58) or = 2 casual condomless partners (AOR 2-4 partners: 3.65 (95% CI: 1.87-7.10); AOR 5-10 partners: 3.34 (95% CI: 1.32-8.49). Age = 35 years was related to less frequent HIV testing (AOR 35-44 years: 0.34 (95% CI: 0.16-0.72); AOR = 45 years: 0.29 (95% CI: 0.12-0.69). PrEP use in the past year was reported by 6.2% (46/744) of MSM and associated with = 2 casual condomless sex partners (AOR: 2.86; 95% CI: 1.17-6.98) or chemsex (AOR: 2.31; 95% CI: 1.09-4.91). Conclusion: This bio-behavioural study of MSM found high rates of behaviours associated with increased risk of HIV transmission. Combination prevention, including frequent HIV testing and use of PrEP, remains crucial in London.