EVALUATION OF THE RATE OF HEPATITIS A IMMUNITY IN A SMALL CITY AFTER THE VACCINATION PROGRAM: ONE CENTER EXPERIENCE

Purpose: Hepatitis A is an infectious disease caused by hepatitis A virus (HAV). Symptomatic infection causes health care costs with loss of labor and school time. HAV outbreaks may cause economic problems by disrupting trade and tourism. The aim of this study is to determine the rate of immunity against HAV infection in a sample of pediatric population. Methods: The study group consisted of all children who underwent anti-HAV IgG evaluation for any reason between January 1, 2012 and December 31, 2020. The data about age, date of birth, sex, residence, vaccination status were retrospectively collected from the hospital record system. Anti-HAV IgG status was determined by chemiluminescent microparticle immunassay kits. The statistical analyses were presented with descriptive methods. Results: Overall 1189 children aged 1-17 years old enrolled to the study. The rate of anti HAV IgG seropositivity was 41.2% in the whole study group. The rates of completed vaccination scheme and seropositivity were 10.7% and 92.2%. Natural immunity rate was 32.6%. Conclusion: The 7-17 age group was found to be susceptible to the acute infection, they were considered as the new target population of vaccination. Vaccination seemed to be the most effective way of providing seropositivity to get rid of acute infection risk and eliminating geographic and socioeconomic differences.