Anal HPV type prevalence in gay, bisexual and other men who have sex with men following an opportunistic HPV vaccination programme in Scotland: a repeated cross-sectional study.

BACKGROUND AND

OBJECTIVES

Gay, bisexual and other men who have sex with men (GBMSM) are at increased risk of anal human papillomavirus (HPV) infection and subsequent development of anal cancer. An opportunistic HPV vaccination programme for GBMSM and those at similar risk for HPV infection was launched in Scotland in July 2017 using the quadrivalent vaccine. We aimed to evaluate the impact of the HPV vaccination programme for GBMSM by monitoring changes in the prevalence of HPV types.

METHODS

A repeated cross-sectional study was undertaken collecting and HPV typing rectal swab samples from men in a city centre sexual health clinic. A baseline sample and three subsequent samples were taken for the 4 years following the introduction of the programme.

RESULTS

Overall, HPV prevalence was high across all sample years, particularly in 2019/2020. Prevalence of quadrivalent vaccine targeted types decreased by 23% (PR 0.77, 95% CI 0.70 to 0.86, p<0.001) in the most recent sample taken in 2021 compared with the baseline. Other high-risk HPV types increased in each sample year and were 25% higher (PR 1.25, 95% CI 1.12 to 1.40, p<0.001) in the 2021 sample compared with baseline.

CONCLUSIONS

Reductions in vaccine targeted types are encouraging and may reflect direct protection offered by the GBMSM vaccination programme or a combination of direct and modest indirect protection from the routine programme. These findings support HPV vaccination as an effective method of anal cancer prevention.