Hepatitis A seroprevalence and demographic risk factors in the susceptible population: a cross-sectional study

OBJECTIVE: The epidemiolo-gy of hepatitis A virus (HAV) infection is influ-enced by variables such as age, sex, environ-mental conditions, and vaccination status. This study aimed to evaluate HAV seropositivity af-ter the inclusion of hepatitis A vaccination in the national childhood immunization program and identify demographic risk factors of the suscep-tible population before routine vaccination. PATIENTS AND METHODS: This cross-sec-tional epidemiological study was conducted by retrospectively examining the laboratory re-cords of patients who underwent HAV serology testing in a tertiary care center in eastern Turkey between 2008 and 2019.RESULTS: Overall immunity to HAV was 81.6%. According to birthplace and year, the rate of anti-HAV positivity was higher among people born before 2006 in the Southeast and Eastern Anatolia regions. For those born in 2012 or later, the lowest seropositivity was among those born in the Southeast region, while it was over 60% in the other regions. When analyzed by year of birth, the lowest seropositivity was in those born between 1994 and 2011, and the fre-quency of seropositivity increased with age. Of those born between 1982 and 1999, the seropos-itivity rate was higher among men than women. Rural dwellers born before 2012 had higher se-ropositivity than urban dwellers. Among those born before the introduction of routine child-hood HAV vaccination, female sex, urban dwell-ing, and each additional year of age were iden-tified as independent demographic risk factors for HAV susceptibility.CONCLUSIONS: Socioeconomic develop-ment and immunization programs have altered HAV seroprevalence patterns. Planning catch-up vaccinations, especially in adolescents and young adults (born in 1994-2011) with low sero-positivity and ensuring the continuity of hygiene and sanitation practices are important to protect the susceptible population.