Enzyme-linked immunoassay for hepatitis B surface antigen. An evaluation of commercial test kits

A commercial, licensed test for hepatitis B surface antigen (HBsAg) based upon an enzyme-linked immunoassay principle was evaluated. The sensitivity, when tested under field conditions, was 0.65 and 0.9 ng/ml for ad and ay subtypes of HBsAg, respectively. Only 0.03 percent of 61,798 units of blood screened were reactive and specific for HBsAg while an additional 0.01% gave nonspecific (nonneutralizable) reactivity.