VIRAL-HEPATITIS

Hepatitis A vaccine is currently under trial. Hepatitis B vaccine has not achieved wide acceptance from adults in the United States. It is recommended that it be included in routine childhood vaccination schedules. Mutations of hepatitis B are being described. One mutation, in the precore region, results in disturbed excretion of e antigen although the patient is hepatitis B virus DNA positive. Another mutation in the surface results in the failure of hepatitis B vaccination. A polymerase chain reaction analysis identifies hepatitis C RNA. This RNA can be found in the serum whether or not anti-hepatitis C virus is present. Hepatitis C is rarely spread by sexual or household contacts or in the perinatal period. The mode of infection in the majority of anti-hepatitis-C-virus-positive patients is unknown. Hepatocellular cancer is a complication of hepatitis virus infection, particularly in Japan. Hepatitis E is an enteric virus that has caused severe epidemics in underdeveloped countries. The viral genome of hepatitis E has been cloned.