Clinical Significance

Transmission of the Hepatitis A virus is via the fecal-oral route, and infection occurs mainly due to contaminated food or poor sanitary conditions.  The virus replicates in the liver and is shed in the stool.  Incubation period ranges from 15-40 days.  Symptoms last approximately 2 weeks and include hepatomegaly, jaundice, dark urine, fatigue, and gastrointestinal disturbances.  At the onset of symptoms, antibody to HAV is detectable, largely compromised of IgM subclass.  HAV IgM is detectable for 3-6 months, but HAV IgG can persist indefinitely.  The anti-HAVG assay is most useful as an aid in the diagnosis of previous hepatitis A infection or in the identification of HAV-susceptible individuals for vaccination.