HPV Catch-up Vaccination is Effective but Cervical Screening Should Continue

This short communication reports additional research that extends the previously published article - Commentary: HPV Catch-Up Vaccination Reduces the Prevalence of HPV 16 and 18 Infections and Cervical Disease: A Retrospective Study.1 One limitation of that study was uncertainty as to whether the catch-up cohort had actually received HPV (human papillomavirus) vaccination. That information has now been obtained. 87 (59%) of the 147 patients in the catch-up cohort had received at least one dose of HPV bivalent vaccine. 69 of these (representing 79% of those vaccinated) had received three doses (as recommended at the time). Both the vaccinated and unvaccinated subsets of the catch-up cohort show a significant reduction in the prevalence of HPV 16 and/or 18 (with/without other high-risk types 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68) and of high grade cervical disease compared to an earlier unvaccinated cohort. These results confirm the efficacy of HPV catch-up vaccination and the existence of herd immunity following the introduction of national HPV vaccination campaigns. However, 34 patients (23%) in the catch-up cohort had high grade disease (cervical intraepithelial neoplasia [CIN] 2 or worse), 16 of whom had been vaccinated (12 with three doses, one with two doses and three with one dose of HPV bivalent vaccine) and four of those vaccinated had HPV 16 and/or 18 (with/without other high-risk types), the rest had other HPV high risk types. This emphasises the importance of maintaining cervical screening alongside HPV vaccination.