Adult use of hepatitis A vaccine in developed countries.

In the industrialized countries of Europe, North America and Australia, the incidence and prevalence of hepatitis A decreased significantly during recent decades. In the high-endemicity areas of Africa, Asia and South America, hepatitis A is still transmitted during infancy or early childhood and usually leads to asymptomatic infection or only mild disease. The majority of infections in developed countries, however, now occur in young adults of whom 70-80% develop more severe icteric disease. Main risk groups in the latter regions are travellers to less-developed areas and drug addicts; an occupational risk of hepatitis A virus infection exists for individuals working in paediatric wards, in day-care centres, in medical laboratories/kitchens as well as for sewage workers. These individuals comprise the target group for active hepatitis A vaccination. Consequent use of these vaccines should not only prevent an often severe disease but also save significant costs.