Immunization, Vaccines and Biologicals

Hepatitis A vaccination should be part of a comprehensive plan for prevention and control of viral hepatitis

A mother and her infant child at the International Centre for Diarrhoeal Disease Research in Dhaka, Bangladesh
UN / David Ohana

In an updated position paper, published in the Weekly Epidemiological Record today, WHO recommends that hepatitis A vaccination be integrated into national immunization schedule for children over the age of one, if indicated on the basis of acute hepatitis A incidence and consideration of cost-effectiveness.

Vaccination should particularly be considered in countries with improving socioeconomic status when there is a change from high to intermediate endemicity and when the age of infection shifts to older age group thus increasing the risk of more severe disease and mortality. In these situations vaccination is likely to be cost-effective. In highly endemic countries where hepatitis A virus is widespread, almost all persons are infected with hepatitis A virus in early childhood, when the infection is asymptomatic or results in very mild disease. In these countries, large-scale vaccination programmes are not recommended.

Vaccination against hepatitis A should be part of a comprehensive plan for the prevention and control of viral hepatitis, including measures to improve hygiene and sanitation and measures for outbreak control. Targeted vaccination of high-risk groups should be considered in low and very low endemicity settings to provide individual health benefits. Groups at increased risk of hepatitis A include travellers to areas of intermediate or high endemicity, those requiring life-long treatment with blood products, men who have sex with men, workers in contact with non-human primates, and injection drug users. In addition, patients with chronic liver disease are at increased risk for fulminant hepatitis A and should be vaccinated.

Recommendations for hepatitis A vaccination in outbreak situations depend on the epidemiologic features of hepatitis A in the community and the feasibility of rapidly implementing a widespread vaccination programme. The use of a single dose regimen of hepatitis A vaccine to control community-wide outbreaks has been most successful in small self-contained communities, when vaccination was started early in the course of the outbreak, and when high coverage of multiple age-cohorts was achieved. Vaccination efforts should be supplemented with health education and improved sanitation.

Hepatitis A is a viral liver disease that can cause mild to severe illness. Globally, there are an estimated 1.4 million cases of hepatitis A every year. The hepatitis A virus is transmitted through ingestion of contaminated food and water, or through direct contact with an infectious person. Hepatitis A is associated with a lack of safe water and poor sanitation. Epidemics can be explosive in growth and cause significant economic losses. Improved sanitation and the hepatitis A vaccine are the most effective ways to combat the disease.

Related links