Prevalence of hepatitis A and B infections in multiply transfused thalassaemic patients.

Evidence of hepatitis B virus (HBV) and hepatitis A virus (HAV) infections was south in 148 multiply transfused patients with thalassaemia and in healthy controls (2040 for HBV and 217 for HAV). The prevalence of the HBV surface antigen or antibody to it was significantly higher in patients than in controls and increased with the number of blood transfusions. In contrast, the prevalence of antibody to HAV was significantly lower in patients than in controls and decreased with the number of blood transfusions. These results support the view that blood transfusion does not play any appreciable part in transmitting HAV. Indeed, regular blood transfusion, where donors almost all have HAV antibody, seems to give protection against infection.