Antibody to the hepatitis B surface antigen in immune serum globulin.

A collection of 1,278 lots of immune serum globulin (ISG) prepared by 19 United States manufacturers between 1962 and 1974 were tested for the hepatitis B surface antigen (HBSAg) and antibody (anti-HBS). Ten lots (0.8%), all of which were produced between 1962 and 1965 by two different manufacturers, were weakly positive for HBSAg (by radioimmunoassay). Seven hundred and seven lots (55.3%) were positive for anti-HBS (by passive hemagglutination). In general, titers of anti- HBS in lots of ISG were low, and the prevalence of anti HBS positive lots varied considerably among different manufacturers. ISG prepared from placental material was more commonly positive for anti-HBS than was ISG prepared from plasma. There was a striking overall increase in prevalence and titer of anti-HBS in ISG lots prepared during 1973 and 1974. This probably reflects the effect of elimination of strongly HBSAg-positive plasma units with the onset of routine screening for HBSAg which began in 1972.