Antibody to the hepatitis B virus-associated delta-agent in immune serum globulins.

Fifty lots of immune serum globulin prepared by four United States manufacturers between 1944 and 1977 were tested for the presence and titer of antibody to the hepatitis B virus-associated delta-agent. Anti-delta was detected in 28 of the 50 lots (56%) of immune serum globulin at titers ranging from 1:10 to 1:400. Anti-delta was present in 75% (6 of 8) of lots produced between 1962 and 1965, in 77% (17 of 21) produced between 1967 and 1970, in 45% (5 of 11) produced between 1971 and 1972 and in none (0 of 9) produced since 1973. A single lot of globulin prepared from plasma that was collected in 1944 from United States Army soldiers also contained detectable anti-delta. These data indicate that delta-infection has been occurring among hepatitis B surface antigen (HBsAg) carriers in the United States since the 1940s. The decrease in prevalence of anti-delta in immune serum globulin lots coincided with the start of routine HBsAg screening of blood and plasma. The elimination of HBsAg-positive units from plasma pools has reduced levels of HBsAg and anti-delta and should have decreased the risk of transmission of both type B hepatitis and delta-hepatitis by plasma products.