Ten-Year Population-Level Impact of Single-Dose Inactivated Hepatitis A Vaccination in Korean Military Recruits: A Nationwide Birth-Cohort Surveillance Study, 2011–2025

Abstract

Using national surveillance data from South Korea, we found lower male-to-female hepatitis A incidence rate ratios in vaccine-era birth cohorts after single-dose military vaccination. Cohort patterns, multivariable regression, and follow-up of the 1996 birth cohort supported persistence of a population-level protective signal beyond military service across a 10-year observation window.