Clinical course and consequences of hepatitis A infection

Hepatitis A virus (HAV) is a small, non-enveloped RNA virus belonging to th e Picornaviridae, for which only one serotype has been identified. Transmis sion is usually through the faecal-oral route by person-to-person contact. The most common risk factors are household or sexual contact with a suffere r, attendance or working at a day-care centre, international travel, and as sociation with food or waterborne outbreaks; 55% of cases have no identifia ble risk factors. HAV infection may be symptomatic or asymptomatic, and sho ws three phases. Virus is shed during the incubation phase, anti-HAV IgM ap pears during the symptomatic phase and can be used for diagnosis, and anti- HAV Ige appears at the same time but persists lifelong. Unusual clinical ma nifestations of hepatitis A include cholestatic, relapsing and fulminant he patitis. Hepatitis A accounts for 93% of cases of acute hepatitis in Argent ina, including 7% of atypical clinical cases. Hepatitis A is the major caus e of fulminant hepatitis, and has been reported to account for 10% of liver transplants in children in France and 20% in Argentina. One-year survival after liver transplantation is 64%. Prevention must be considered as the ma in means of averting this severe illness. (C) 2000 Published by Elsevier Sc ience Ltd. All rights reserved.