Hepatitis A is caused by a virus resulting from an acute inflammation of the liver; it is the most common form of all viral hepatitis. It is encountered frequently in the most disadvantaged geographical regions. Generally, this inflammation is a result of a lack of safe water, and poor sanitation and hygiene. It is encountered frequently in urban areas but the incidence rates differ according to geographical regions and socio-economic levels.

Despite progress in sanitation and hygiene, hepatitis A occurs sporadically and in epidemics worldwide, with a tendency for cyclic recurrences. The disease can lead to significant economic and social consequences in communities. The impact on food establishments identified with the virus, and local productivity in general, can be substantial.

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Approximately 1.4 million cases are reported each year 2


  1. a ST. Hepatitis A virus seroprevalence by age and world region, 1990 and 2005. Vaccine 28 (2010) 6653–6657.
  2. WHO. Hepatitis A. Immunization, Vaccines and Biologicals, 2015; Accessed January 2018. http://www.who.int/immunization/diseases/hepatitisA/en/
  3. WHO. Hepatitis A Fact sheet. Revised July 2017, accessed January 2018. http://www.who.int/mediacentre/factsheets/fs328/en/

This page last update: 09-2019