The hepatitis A virus is a Heparnavirus of the Picornaviridae family causing Hepatitis A infection. The virus, which is transmitted primarily by the foecal-oral route, is spread by close person-to-person contact and by food- and water-borne epidemics. There is little or no evidence of transplacental transmission from mother to fetus or transmission to newborn during delivery. Common symptoms include malaise, loss of appetite, nausea and icterus. Symptoms, which are often mild and even subclinical, usually resolve within two to four weeks of onset. Recovery is complete, with no chronic sequelae, and long-lasting, usually lifelong, immunity results. The hepatitis A antigen (HAV antigen) is present in stool about one to two weeks before onset of clinical symptoms and for about one week afterwards. After HAV antigen is no longer detectable in stool, antibodies to HAV antigen (anti-HAV) are found in serum and persist for the life of the patient, conferring long-lasting immunity to HAV reinfection.