Vaginal and anal human papillomavirus infection and seropositivity among female sex workers in Amsterdam, the Netherlands: Prevalence, concordance and risk factors.

BACKGROUND: We studied prevalence, risk factors and concordance of vaginal and anal HPV infection and L1 seropositivity among female sex workers (FSW) in Amsterdam. METHODS: In 2016, FSW aged ≥18 years having a sexually transmitted infections (STI) consultation were invited to participate. Participation entailed taking vaginal and anal self-swabs. Demographics and sexual behaviour data were collected. HPV DNA was analysed using the SPF10-PCR-DEIA-LiPA25-system-v1. Serum was tested for HPV L1 antibodies using multiplex serology assays. Determinants of vaginal and anal high risk HPV (hrHPV) infection and L1 seropositivity were assessed with logistic regression analyses. RESULTS: We included 304 FSW; median age was 29 years (IQR 25-37). Vaginal and anal hrHPV prevalence were 46% and 55%, respectively. HrHPV L1 seropositivity was 37%. Vaginal-anal hrHPV concordance was strong, but no significant association between vaginal or anal hrHPV infection and seropositivity was found. Having had anal sexual contact was not associated with anal hrHPV infection (P = 0.119). DISCUSSION: Vaginal and anal hrHPV prevalence is high among FSW in Amsterdam, the Netherlands. Promotion of HPV vaccination, preferably at the beginning of the sex (work) career, may be a useful prevention method against hrHPV infection and disease.