How the HPV Shot Shields Everyone!

A large, long-term study conducted by researchers at Albert Einstein College of Medicine and collaborating institutions evaluated the real-world impact of human papillomavirus (HPV) vaccination on infection rates among adolescent and young adult women over a 17-year period. The findings, published in JAMA Pediatrics, provide compelling evidence for both direct vaccine efficacy and herd protection in community settings.¹

HPV is the most prevalent sexually transmitted infection worldwide and the principal cause of cervical cancer. It also contributes to other anogenital malignancies and head and neck cancers, with over 690,000 new cases attributed to HPV annually—representing 4.5% of the global cancer burden. Randomized clinical trials have demonstrated strong protective efficacy of HPV vaccines, but those trials often enrolled lower-risk populations. Thus, this study aimed to assess effectiveness in a broader community cohort with diverse risk profiles.¹

Between 2006 and 2023, six consecutive studies were conducted in Cincinnati, involving 2,335 females aged 13–26 years. Participants reported high-risk behaviours—79% had two or more male partners and 51% reported at least one previous sexually transmitted infection. Vaccination uptake increased from 0% at baseline to 82% by 2023, with participants receiving at least one dose of the bivalent, quadrivalent, or nonvalent HPV vaccines.

As vaccination rates rose, infections from vaccine-targeted HPV types declined significantly among vaccinated participants: 98.4% reduction for bivalent types (16,18), 94.2% for quadrivalent types (6,11,16,18), and 75.7% for nonvalent types (adding 31,33,45,52,58) [1]. These findings align with global systematic reviews showing marked decreases in HPV prevalence and related disease following widespread vaccination.²

Importantly, unvaccinated women also experienced substantial declines in HPV infections, reflecting herd immunity. Rates of vaccine-covered infections dropped by 71.6% for bivalent types and 75.8% for quadrivalent types among unvaccinated participants. This effect is attributed to decreased community transmission resulting from high vaccination coverage in both males and females.

The study reinforces that reductions in HPV infection were not due to behavioural changes but directly linked to vaccination. It further underscores the public health potential of HPV immunization in preventing cervical cancer and other HPV-associated malignancies. However, global disparities remain; while coverage in the Americas reaches 68%, only 1% of girls are vaccinated in the Eastern Mediterranean region.³

The authors conclude that expanding global HPV vaccine uptake, alongside screening and treatment, could make cervical cancer elimination a realistic public health achievement.

References:

1. Kahn JA, Brown DR, Brown VN, Moscicki AB, Rosenthal SL, et al. Population-level effectiveness and herd protection 17 years after human papillomavirus vaccine introduction. JAMA Pediatr. 2025;179(9):xxx-xxx. doi:10.1001/jamapediatrics.2025.2828
   
   
2. Drolet M, Bénard É, Pérez N, Brisson M, Ali H, Boily M-C, et al. Population-level impact and herd effects following the introduction of human papillomavirus vaccination programmes: updated systematic review and meta-analysis. Lancet. 2019;394(10197):497–509. doi:10.1016/S0140-6736(19)30298-3.
   
   
3. Albert Einstein College of Medicine. Study shows HPV vaccine protects vaccinated—and unvaccinated [Internet]. EurekAlert!; 2025 Mar 10 [cited 2025 Sep 30]. Available from: https://www.eurekalert.org/news-releases/1099993