Vaccination of travelers against hepatitis A and B.

Despite the fact that effective preventive measures have become available, there has been no decline in the incidences of both hepatitis A and hepatitis B in most industrialized countries to date. This is, in part, due to the rapid increase in the number of travelers to areas of medium and high endemicity for both diseases, primarily developing countries. Targeting of travelers at risk of contracting these diseases for vaccination offers a chance of significantly reducing their incidence. Hepatitis A, an acute disease associated with poor food hygiene, is the most common vaccine-preventable infection in travelers. Hepatitis A immunity should, therefore, be considered essential for anyone visiting an area of high endemicity. In contrast, hepatitis B is a blood-borne virus which was thought, until recently, to pose a relatively low risk to the majority of travelers. However, the 1990s has seen international tourism and business travel grow faster in Europe than anywhere else in the world, with travel to areas of high endemicity for hepatitis B (Africa, Asia and South America) being commonplace. Thus the number of reported hepatitis B cases is increasing in many countries. Furthermore, there is considerable overlap of high-endemicity areas of hepatitis A and hepatitis B so that travelers are often considered to be at risk from both viruses. As well as separate hepatitis A and B vaccine preparations, a combined hepatitis A and B vaccine is now available which may offer improvements in vaccination schedule, enhanced patient compliance, and reduced cost.