Hepatitis A

Vaccination against hepatitis A should be part of a comprehensive plan for the prevention and control of viral hepatitis, including measures to improve safe drinking-water, sanitation and hygiene (such as hand washing) and measures for outbreak control.

WHO recommends that vaccination against hepatitis A virus be introduced into national immunization schedules for individuals aged ≥12 months, if indicated on the basis of: i) an increasing trend over time of acute hepatitis A disease, including severe disease, among older children, adolescents or adults; ii) changes in the endemicity from high to intermediate; and iii) considerations of cost–effectiveness.

For children, inactivated hepatitis A vaccines can be given as a single- or two-dose (off-label) schedule, and administered intramuscularly. With a two-dose schedule, the first dose should be given starting from age ≥12 months.

In highly endemic countries, most individuals are asymptomatically infected with HAV in childhood, which prevents clinical hepatitis A in adolescence and adulthood. In these countries, large-scale hepatitis A vaccination programmes are not routinely recommended, because they carry a risk of a paradoxical increase in disease incidence in unvaccinated people.

Countries with improving socioeconomic status may rapidly move from high to intermediate hepatitis A endemicity, rendering a larger proportion of the adolescent and/or young adult population susceptible to HAV infection. In such countries, large-scale hepatitis A vaccination in early childhood is likely to be cost–effective and is therefore recommended.

Hepatitis B

Several hepatitis B vaccines are available internationally. Both monovalent and products with multiple antigens are highly immunogenic and vaccination in a series of three doses will generate long-lasting, possibly life-long, protection against hepatitis B.

Vaccination against hepatitis B should be part of a comprehensive plan for the prevention and control of viral hepatitis, including measures for blood safety.

WHO recommends that all infants should receive their first dose of Hepatitis B vaccine as soon as possible after birth, preferably within 24 hours. The birth dose should be followed by 2 or 3 doses to complete the primary series.  WHO also recommends that all health care workers receive this vaccine to prevent the risk of Hepatitis B in health care settings.

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Hepatitis E

Currently, there are no WHO pre-qualified vaccines against hepatitis E. In 2011, the first vaccine to prevent hepatitis E infection was registered in China.

A Strategic Advisory Group of Experts (SAGE) on Immunization Working Group on Hepatitis E was established in October 2013 to review the existing data on the safety, immunogenicity, efficacy, and cost-effectiveness of the hepatitis E vaccine. The target date for publication of the WHO position paper on hepatitis E vaccine is early 2015.

In the absence of internationally available vaccines, WHO recommends prevention of hepatitis E infection and transmission by maintaining quality standards for public water sources and proper disposal of sanitary waste, as well as maintenance of personal hygiene practice and avoiding drinking water and/or ice of unknown purity while in areas of high endemicity.

WHO Health Topic

Prequalified vaccines