Seroprevalence of hepatitis A virus antibodies (anti-HAV) in adult inhabitants of Wielkopolska region, Poland - the role of simple demographic factors

Introduction and objective: Based on the available epidemiologic data, Poland currently has the features typical for areas of very low endemicity for hepatitis A. The incidence of hepatitis A in the Wielkopolska region in years 2006-2008 was 0.68/100,000 inhabitants or significantly lower. The aim of this cross-sectional analysis was to evaluate the seroprevalence of anti-HAV antibodies in inhabitants of the Wielkopolska region of western Poland regarding some demographic factors. Material and methods: In addition to testing anti-HAV antibodies, the medical history and demographic data, such as age, gender, place of residence, and level of education of 680 patients and 105 healthy blood donors were analyzed. Results: Anti-HAV antibodies were observed in 235 cases (29.9%). In univariate regression analysis, the covariates correlated with positive anti-HAV testing were age, female gender and lower level of education. Only 6.2% of young adults were seropositive. Among study participants above the age of 50, anti-HAV antibodies were present in 64-100% of cases. An icteric disease consistent with hepatitis A diagnosis was identified in the histories of 10.2% of seropositive patients. Conclusions: The risk for contracting disease after exposure to HAV in young (<40 years old) inhabitants of the Wielkopolska region is high. Apart from older individuals, also women and people with a lower level of education are more frequently seropositive. A low level of immunity to HAV should be an indication for vaccination against HAV, especially in selected groups.