Update on prevention and treatment of viral hepatitis in children.

Viral hepatitis is a persisting concern. Outbreaks of hepatitis A occur in developed countries where only 10% to 20% of the population is seroprotected. The disease may cause fulminant liver failure and death. People who are targeted for vaccination include intravenous drug users, homosexuals, and chronic hepatitis patients. Secondary prophylaxis of household contacts is an efficient way to prevent secondary cases. Universal vaccination is now in progress for hepatitis B. Vaccination failure may occur in low birth weight infants, or in infants infected in utero. Chronic carriers of viral hepatitis may progress to cirrhosis and hepatocarcinoma, the latter risk being most important for men infected at birth. Alcohol intake should be avoided in carrier adolescents. Interferon is able to triple the rate of hepatitis B e antigen loss and decouple the rate of hepatitis B s antigen loss after one year, shortening disease evolution and, it is to be hoped, decreasing the risk of unfavorable outcome. Similarly, lamivudine increases by four times the rate of hepatitis B e antigen loss in adults. However, precore mutants may be selected by immune pressure after seroconversion in children, and tyrosine-methionine-aspartate-aspartate (YMDD) mutations appear in 15% of patients treated with lamivudine after 1 year. Hepatitis C is mainly acquired during childhood via true vertical transmission. The risk of acquiring Hepatitis C is related to the presence and amount of RNA for hepatitis C virus in mothers at the time of birth. The infection rate for the hepatitis C virus is higher in children from mothers who have tested positive for HIV, and higher if these children are themselves coinfected with HIV. Treatment with interferon alone has a poor rate of efficiency, although pediatric studies remain scarce. Combination treatment using ribavirin plus interferon yield a higher rate of success in eradicating viral infection in adults.