Virus hepatitis B, A, non-A, non-B.

Hepatitis B vaccine is safe and effective. Its impact on the prevention of the disease, however, has been limited. In high risk areas, such as the Far East, mass vaccination of all babies is recommended. Even in low risk areas, such as Northern Europe and the United States, vaccination as part of a routine childhood immunisation programme might be effective so that protection is given before the adult becomes at risk of drug abuse or becoming a promiscuous homosexual or has joined the Health Care Service. A booster injection is probably necessary 5-7 years after primary vaccination. Hepatitis A still causes enormous epidemics. In Western Europe, large numbers of adults are at risk and the economic consequences are considerable. Vaccines which will replace serum immune globulin prophylaxis are under development. Epidemic non-A, non-B hepatitis is caused by a 27-34 nm virus, enterically transmitted. An antibody can be detected in the serum of sufferers from the epidemic but not the sporadic disease. Parenteral non-A, non-B hepatitis is associated with a viral genomic clone, isolated from infected chimpanzee liver and plasma. An antibody to it has been shown in serum of infectious blood donors and in haemophiliac patients previously exposed to blood products.