Yuna Lim
Konkuk University
"Comparison of the Effectiveness and Costs of Hepatitis A Vaccination Strategies by Age in the Republic of Korea"
Improved hygiene conditions by economic growth and the introduction of the national immunization program for infants have led to variations in hepatitis A antibody prevalence across age groups in Korea. Specifically, individuals in their 20s to 40s have the lowest antibody prevalence. Given that the fatality rate of hepatitis A increases with age, the low immunity level among young adults suggests that, without additional preventive interventions, there is a risk of increased deaths in older age groups in the future. We developed an age-structured transmission model that accounts for age-specific antibody prevalence and fatality rates to assess the impact of adult vaccination, assuming it starts in 2025. We compared vaccination strategies targeting individuals in their 20s to 30s and those in their 40s to 50s, considering that antibody testing costs are incurred for the latter group in Korea. Our study shows that when total costs for vaccination are fixed, vaccinating individuals in their 40s to 50s covers 0.2 times fewer individuals than vaccinating those in their 20s to 30s but reduces deaths by 1.3 to 1.5 times more. When the total vaccine supply is fixed, the total and annual costs of vaccinating individuals in their 40s to 50s are 1.2 times higher than those for the 20s to 30s group, while the reduction in deaths is 1.7 to 1.8 times greater. From the perspective of reducing deaths, vaccinating individuals in their 40s to 50s is more effective than vaccinating those in their 20s to 30s. Furthermore, our research suggests that if an additional vaccination intervention is introduced for individuals in their 20s to 30s, military personnel may continue to receive only a single-dose vaccination, as is currently practiced.
Note: this minisymposia has been accepted, but the abstracts have not yet been finalized.
Annual Meeting for the Society for Mathematical Biology, 2025.