Prevalence of and factors associated with anal high-risk human papillomavirus in urban Tanzanian men who have sex with men, 2011-2012

Background: Anal cancer is primarily caused by high-risk human papillomavirus (hrHPV), is associated with HIV infection, and has a very high incidence among men who have sex with men (MSM). We assessed prevalence of hrHPV, and factors associated with hrHPV in anal canal specimens collected in Dar es Salaam, Tanzania from HIV-positive and HIV-negative MSM. Methods: MSM were recruited using respondent-driven sampling in this cross-sectional study. The primary outcome in this ancillary analysis of 116 MSM was prevalence of HPV-16 and other hrHPV types. Prevalence ratios (PR) estimated the association between hrHPV and HIV-negative participants’ demographics, sexual behaviour and sexually transmitted infections. Results: Median age was 23 years and 33.6% of participants were HIV-positive. HrHPV and HPV-16 prevalence was 54.3% and 17.2%, respectively, with HPV-16 prevalence highest among HIV-positive MSM identifying as gay (36.1%) and lowest among HIV-negative MSM identifying as bisexual (2.9%). Having two or more receptive anal sex partners in the past month was associated with hrHPV (PR 3.20, 95%CI 1.69-6.07, vs. 0 partners) among HIV-negative MSM.Conclusions: HrHPV prevalence was high among MSM in Dar es Salaam and highest among HIV-positive MSM identifying as gay. These estimates may be used to support HPV vaccination and screening initiatives.