The Gambia Hepatitis Intervention Study. The Gambia Hepatitis Study Group.

The Gambia Hepatitis Intervention Study is a large-scale vaccination project in The Gambia, initiated in July 1986, in which the introduction of national hepatitis B (HBV) vaccination of young infants progressively over a 4-year period is proposed. During this time it is anticipated that about 600,000 infants will receive a course of HBV vaccine and a similar number will not receive the vaccine. All children in the study will receive the normal childhood vaccinations. Identification data for each child will be collected and stored with information on their vaccination records. A national surveillance system will be set up to detect new cases of hepatocellular cancer and other chronic liver diseases over a period of 30 to 40 years. An attempt will be made to trace each case, of relevant age, to determine if they are included in the HBV vaccination study. In this way, the efficacy of HBV vaccine in the prevention of HCC and chronic liver diseases will be evaluated. Details of the study design are discussed.