Risk of hepatitis A infection following travel.

Abstract

Travel to endemic areas is one of the most frequently reported risk factors for infection with the hepatitis A virus (HAV). We evaluated the association between HAV infection and travel, by area of destination. We conducted a case-control study on all cases of HAV infection reported to the Italian National Surveillance System for Acute Viral Hepatitis in the period 1996-2000. The study population consisted of 9695 persons with HAV infection (cases) and 2590 with HBV infection (controls). The risk of acquiring HAV was highest for travel to Asia, Africa and Latin America [Odds Ratio = 9.30 (95%CI = 6.71-12.9)]; a three-fold statistically significant excess of risk was found for travel to southern Italy (OR = 3.03) and to the Mediterranean Area and Eastern Europe (OR = 3.15). Travel was implicated in 28% of the cases of HAV infection. When stratifying the analysis by area of residence (northern and central Italy vs southern Italy and the Islands), the above-mentioned risks were confirmed only for those residing in northern and central Italy, with no significant risk for those residing in southern Italy and the Islands. Travel to areas endemic for HAV infection constitutes a considerable risk. Our results highlight the importance of developing health policies for improving environmental and hygienic conditions, as well as the prevention of certain eating habits. Vaccination before travelling to a medium or high endemic area could be a safe and effective means of preventing travel-related HAV infection.