Hepatitis A

Hepatitis A is caused by a virus (HAV) that leads to an acute inflammation of the liver and is the most common form of all viral hepatitis. Hepatitis A is encountered frequently in the most disadvantaged geographical regions. Improvements in hygiene and sanitation have led to a reduction in the circulation of the virus, but not to its complete disappearance.

Symptoms of hepatitis A

  • Hepatitis A is often asymptomatic in young children, and more severe in adults. After an incubation period of 14 to 28 days, the onset of the disease is marked by a sensation of generalized malaise including, fever, headache, muscle soreness, fatigue, and gastrointestinal disorders. It is often accompanied by jaundice, particularly in adults.(1)
  • The condition may be long-lasting, with an acute phase of approximately one month and a convalescence phase of up to six months.
  • No specific treatment is available.

Epidemiology and vaccination against hepatitis A

  • Hepatitis A is a strictly human disease. Transmission occurs through the fecal-oral route, from person to person, or by ingestion of contaminated food or drinking water.
  • Approximately 1.4 million cases are reported each year.(2)
  • Hepatitis A is most common in urban areas but the incidence rates differ according to geographical regions and socio-economic levels.
  • Hepatitis A vaccines are available.


1 - WHO. Hepatitis A Fact sheet. Revised July 2017, accessed January 2018. http://www.who.int/mediacentre/factsheets/fs328/en/

2 - WHO. Hepatitis A. Immunization, Vaccines and Biologicals, 2015; Accessed January 2018. http://www.who.int/immunization/diseases/hepatitisA/en/