HEPATITIS

Viral hepatitis, due to the A, B, C, D, and E hepatitis viruses, is probably the world's commonest viral illness. Through the B and C viruses, in particular, it is also responsible for many cases of primary hepatocellular carcinoma, one of the commonest malignant tumours. The hepatitis B virus alone is believed to be second only to tobacco among human carcinogens.1 Thus the development of effective vaccines is of the highest priority. Most of the vaccines covered in this series have been developed by attenuating, inactivating, and partly purifying candidate viruses. While this approach has also been of value in the preparation of vaccines against hepatitis A virus infection, lack of knowledge of the viral structure or inability to grow the viruses in tissue culture has greatly impeded the development of vaccines against the other hepatitis viruses. Against this background, the enormous success of the hepatitis B vaccination programme now established in many countries is a testament to the ingenuity of the scientific approach. © 1990.