Hepatitis B virus and hepatitis B surface antigen in human albumin products

A collection of 1,985 lots of normal serum albumin (NSA) and 1,361 lots of plasma protein fraction (PPF) prepared between 1958 and 1974 were tested for the presence of hepatitis B surface antigen (HBsAg). Twenty-one percent of NSA lots and 71 per cent of PPF lots were HBsAg-positive by radioimmunoassay. There was considerable variation in frequency of HBsAg-positive lots among the 17 different manufacturers of NSA and the six manufacturers of PPF. In general, those lots prepared from volunteer donor plasma and placental material demonstrated lower rates of HBsAg-positivity than those prepared from commercial donor plasma. A striking decrease in the prevalence of HBsAg-positive lots of both NSA and PPF occurred during the period 1971 to 1973, coincident with the onset of routine screening of all plasma for HBsAg. Although NSA and PPF can be HBsAg-positive, they probably do not transmit type B hepatitis. Serologic tests for HBsAg and antibody to HBsAg revealed that albumin products prepared from infectious, icterogenic plasma were infectious prior to pasteurization, but that they no longer transmitted type B hepatitis after heat treatment at 60 C for ten hours.