Hepatitis E infection in children: study of an outbreak.

Background: Hepatitis E virus (HEV) is responsible for most of the hepatitis epidemics in the developing world and it frequently affects young adults. Therefore, common perception is that it does not affect children. Methods: A group of 20 school children (13 years old) were possibly exposed to hepatitis E virus infection during a 2 day trekking trip. Epidemiological and clinical information was correlated to the presence of the hepatitis E virus genome and antibodies to HEV structural and non-structural proteins found in the blood of the children, using polymerase chain reaction and line immunoassay techniques. Results: Ten children developed icteric hepatitis, seven prodrome-like illness without jaundice while three remained asymptomatic. Immunoglobulin M (IgM) antibodies to open reading frame (ORF)2 protein (pORF2) were detected in all 19 children tested, whereas 11 and 10 of the children were positive for IgM antibodies against ORF1 (pORF1) and ORF3 (pORF3) proteins, respectively. The rate of HEV infection was found to be 85%. Viraemia was observed in 11 children and was present in four of the seven anicteric patients (55%) compared with six of the nine (66%) icteric patients. One child without any symptom also had viraemia. Conclusions: The data obtained indicate a high susceptibility of children for HEV infection and a frequently prolonged viraemia in those infected. © 1999 Blackwell Science Asia Pty Ltd