Factors Related to Completed Status and Seropositivity of Hepatitis A Immunization Among Children Aged 1–3 Years and 6–8 Years in South Korea

This study was designed to identify factors associated with hepatitis A immunization status and seropositivity in Korean children. In-person interviews, reviewing their vaccination cards and testing hepatitis A antibody were conducted with 389 children aged 1–3 years and 544 children aged 6–8 years. In all age groups, earlier birth order was the only significant factor in children receiving either single or both doses of the vaccination. And completion of the second dose of vaccination was a prerequisite for increased seropositivity. Additionally, household income had a positive impact on seropositivity only in children aged 6–8 years. Our findings suggest that presence of an economic barrier is the underlying cause of the decreased hepatitis A vaccination services in Korea. Therefore, hepatitis A vaccine should be included in the essential National Immunization Program.