Prevalence and correlates of anal HPV infection among men who have sex with men in Brazil: A respondent-driven sampling study.

OBJECTIVES

Human papillomavirus (HPV) is the main cause of anal carcinoma, whose incidence is rising globally, especially among men who have sex with men (MSM). This study estimated anal HPV prevalence, investigated genotype distribution, and identified associated factors among MSM in Brazil.

METHODS

The SMESH study, a multicenter cross-sectional survey (2019-2023), analyzed 1375 MSM (≥18 years) from nine Brazilian capitals using respondent-driven sampling. Participants completed questionnaires and provided self-collected anal samples for HPV detection. Weighted analyses were applied.

RESULTS

Anal HPV prevalence was 72.4% (95% CI: 67.6-77.3), with 62.3% (95% CI: 56.9-67.8) harboring high-risk HPV and 36.4% (95% CI: 30.9-41.8) infected with quadrivalent vaccine types. MSM living with HIV (18.1%), compared to HIV-negative MSM, had higher overall (87.7% vs 69.6%, P < 0.001) and high-risk HPV prevalence (78.9 vs 58.9%, P < 0.001). Vaccinated MSM presented lower rates of quadrivalent vaccine types, particularly HPV 16. Younger age (25-34 years), frequent group sex, and regular drug use during sex were associated with HPV infection.

CONCLUSION

The high prevalence of anal HPV among Brazilian MSM highlights the importance of expanding HPV vaccination coverage, particularly for HIV-positive MSM, and reinforces the need for gender-neutral vaccination of all girls and boys before sexual debut.