In Turkey Hepatitis A virus (HAV) infection is considered to be moderateendemic. Hepatitis A vaccine was included in the mandatory vaccination schedule of Turkey on November 2012. We aimed to evaluate the cases of HAV infection followed in Ankara, which is located in the center of Central Anatolia, retrospectively according to the date of the administration of the mandatory hepatitis A vaccine. A total of 272 children followed-up between January 2008 and December 2015 for HAV infection in five separate hospitals were enrolled to the study. There were 200 (68.2%) cases in the pre-vaccination group, 72 (31.74%) cases in the post-vaccination group, and 55.1% were male in total. The immunization status were as follow; 89.7% (n = 244) unvaccinated, 0.4% (n = 1) vaccinated and 9.9% (n = 27) with unknown immune status. There was a statistically significant difference between the groups in hospitalization rates, but no statistically significant differences in hospitalization indications, length of hospital stay, complication types and proportions, and normalization period of transaminases. The national hepatitis A immunization program in Turkey has had a significant impact when the targeted population is considered, with suggestive herd protection effects.

Keywords: Hepatitis A vaccine, children, immunization program, impact