Work

Trends in Routine First-Dose Human Papillomavirus Vaccination Coverage in Wakayama Prefecture, Japan, Fiscal Years 2020–2025

Year: 2026

Type: preprint

Abstract: Background In Japan, proactive recommendations for human papillomavirus vaccination were suspended in 2013 and resumed in fiscal year 2022 alongside a catch-up program, whose first-dose eligibility ended in fiscal year 2024. Coverage among subsequent routine-vaccination cohorts remains unclear. We described first-dose vaccination coverage in Wakayama Prefecture during fiscal years 2020–2025, focusing on grade-specific differences between 2024 and 2025. Methods This descriptive epidemiological study used aggregated administrative data. Age-specific first-dose counts were obtained from e-Stat for fiscal years 2020–2021 and the Wakayama Prefectural Government for 2022–2025. Denominators were age-specific female populations from the 2020 Population Census. Vaccination counts and population data were reconstructed by birth fiscal year using a published method. Annual and cumulative coverage were estimated for the 2004–2013 birth cohorts. Results Between fiscal years 2024 and 2025, annual coverage changed from 3.8% to 4.1% in sixth-grade elementary school students, 20.6% to 15.4% in first-year junior high school students, 2.2% to 7.7% in second-year junior high school students, 30.5% to 16.4% in third-year junior high school students, and 13.1% to 6.1% in first-year high school students. Cumulative coverage by the end of first-year high school was 46.5% and 49.9% for the 2008 and 2009 birth cohorts, respectively. The highest-coverage grade shifted from first-year high school to third-year junior high school. Conclusions The predominant timing of first-dose vaccination shifted toward younger grades during fiscal years 2020–2025. However, annual coverage in 2025 was lower than in 2024 among first- and third-year junior high school students and first-year high school students.

Source: Research Square

DOI: 10.21203/rs.3.rs-11382214/v1