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.