Travel-associated hepatitis A: effect of place of residence and country visited.

The association between hepatitis A and domestic or international travel from Italy was investigated. Data from a nationwide surveillance system (SEIEVA) for type-specific acute viral hepatitis were used to compare 1102 hepatitis A cases with 3671 hepatitis B cases. An association between hepatitis A and travel was found in northern Italy, where most young and adult people are susceptible. Estimates of odds ratios vary dramatically according to geographical area of travel. Travellers to Mediterranean countries, Eastern Europe, Africa, Asia, and South and Central America had the highest education and age-adjusted odds ratios for hepatitis A, ranging from 6 to 25. Prophylaxis against hepatitis A for such travellers is recommended.