Sometimes called a travel disease, hepatitis A is the most frequently occurring, vaccine-preventable infection in travelers. The incidence rate for unprotected travelers is estimated to be 3 to 5 per 1000 travelers per month of stay in a developing country. In fact, the rate can be as high as 20 per 1000 per month for travelers eating and drinking under poor hygienic conditions (e.g., street vendors).

The incidence of hepatitis A disease in travelers increases with the length of their visit and is highest for those who stay in or visit rural areas, trek in back country, or frequently eat or drink in areas with poor sanitary conditions. However, many travelers falsely assume that the risk of hepatitis A is present only under these conditions. In fact, hepatitis A can also occur among travelers who stay only in urban areas and luxury hotels.