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Background In the Netherlands, the bivalent HPV vaccine (2vHPV) has been offered to preadolescent girls via the National Immunization Program (NIP) in a two-dose (2D) schedule since 2014. The current study estimates vaccine effectiveness (VE) against HPV infections up to four years post-vaccination among girls eligible for routine 2D immunization. Methods A cohort study (HAVANA2) was used in which participants annually filled out an online questionnaire and provided a vaginal self-sample for determination of HPV by the SPF10-LiPA25 assay, able to detect 25 HPV types. VE against incident type-specific infections and pooled outcomes was estimated by a Cox proportional hazards model with shared frailty between the HPV types. Results In total, 2027 girls were included in the study, 1098 (54.2%) of whom were vaccinated with two doses. Highest incidence rate was 5.0/1000 person-years (HPV51) among vaccinated participants and 9.1/1000 person-years (HPV74) among unvaccinated participants. Adjusted pooled VE was 84.0% (95%CI, 27.0-96.5%) against incident HPV16/18 infections and 86.5% (95%CI, 39.5-97.08%) against cross-protective types HPV31/33/45. Conclusion Four years post-vaccination, two doses of 2vHPV vaccination were effective in the prevention of incident HPV16/18 infections and provided cross-protection to HPV31/33/45. Our VE estimates rival those from three-dose schedules, indicating comparable protection by 2D schedules.

BackgroundIn many countries, HIV pre-exposure prophylaxis (PrEP) users are screened quarterly for STIs. We assessed the consequences of less frequent STI testing. We also assessed determinants of asymptomatic STI and potential for onward transmission.MethodsUsing data from the AMPrEP study, we assessed the proportion of syphilis, and genital, anal, and pharyngeal chlamydia and gonorrhoea diagnoses which would have been delayed with biannual versus quarterly screening. We assessed the potential for onward transmission by examining reported condomless anal sex (CAS) in periods after to-be-omitted visits when screening biannually. We assessed determinants of incident asymptomatic STIs using Poisson regression and calculated individual risk scores on the basis of the coefficients from this model.ResultsWe included 366 participants. Median follow-up was 47 months (IQR 43–50). 1,183STIs were diagnosed, of which 932(79%) asymptomatic. With biannual screening, 483 asymptomatic STIs (52%) diagnoses would have been delayed at 364 study visits. Of these visits, 129 (35%), 240 (66%) and 265 (73%) were followed by periods of CAS with steady, known casual or unknown casual partners, respectively. Older participants had a lower risk of asymptomatic STI (incidence rate ratio (IRR) 0.86/10-year increase, 95% CI 0.80 to 0.92), while CAS with known (IRR 1.36, 95% CI 1.10 to 1.68) and unknown (IRR 1.86, 95% CI 1.48 to 2.34) casual partners and chemsex (IRR 1.51, 95% CI 1.28 to 1.78) increased the risk. The individual risk scores had limited predictive value (sensitivity=0.70 (95% CI 0.66 to 0.74), specificity=0.50 (95% CI 0.48 to 0.51)).ConclusionReducing the STI screening frequency to biannually among PrEP users will likely result in delayed diagnoses, potentially driving onward transmission. Although determinants for asymptomatic STIs were identified, predictive power was low.

Background Cervical cancer is a major public health problem in India, where access to prevention programmes is low. The World Health Organization-Strategic Advisory Group of Experts recently updated their recommendation for human papillomavirus (HPV) vaccination to include a single-dose option in addition to the two-dose option, which could make HPV vaccination programmes easier to implement and more affordable. Methods We combined projections from a type-specific HPV transmission model and a cancer progression model to assess the health and economic effects of HPV vaccination at national and state-level in India. The models used national and state-specific Indian demographic, epidemiological and cost data, and single-dose vaccine efficacy and immunogenicity data from the IARC India vaccine trial with 10-year follow-up. We compared single- and two-dose HPV vaccination for a range of plausible scenarios regarding single-dose vaccine protection, coverage and catch-up. Results Under the base-case scenario of life-long protection of single-dose vaccination in 10-year-old girls with 90% coverage, the incremental cost-effectiveness ratio (ICER) of nationwide vaccination relative to no vaccination was $405 per DALY averted and lay below an opportunity-cost based threshold of 30% Indian GDP per capita in each state (state-specific ICER range: $67 to $593 per DALY averted). The ICER of two-dose vaccination versus no vaccination and versus single-dose vaccination was $1403 and minimum $2279 per DALY averted, respectively. Conclusions Nationwide introduction of single-dose HPV vaccination in India is highly likely to be cost-effective whereas extending the number of doses from one to two would have a less favourable profile.