Search

Presents information on a study that examined hepatitis C virus infection among hospital employees with needlestick injuries. Research methods; Results and discussion.

A microtitre solid-phase blocking radioimmunoassay (RIA) for antibody to the hepatitis B virus (HBV)-associated delta antigen was specific and detected anti-delta antibody at dilutions of serum of up to 10(6). Analysis of sera from HBsAg-negative subjects and different categories of HBsAg carriers from different regions confirmed the association of anti-delta antibody with HBV infection. Anti-delta antibody was detected in persistently high titres in 19.1% and 2.6% of sera from patients with chronic hepatitis and symptomatic chronic carriers, respectively, and was not detected in the sera of HBsAg-negative controls. Anti-delta antibody appeared transiently and in low titres (less than 1:500) in 4.8% of sera from patients with acute type B hepatitis. The presence and persistence of anti-delta antibody seem to be associated with chronic HBV infection and the development of progressive liver damage.

A specific assay has been developed for a blood-borne non-A, non-B hepatitis (NANBH) virus in which a polypeptide synthesized in recombinant yeast clones of the hepatitis C virus (HCV) is used to capture circulating viral antibodies. HCV antibodies were detected in six of seven human sera that were shown previously to transmit NANBH to chimpanzees. Assays of ten blood transfusions in the United States that resulted in chronic NANBH revealed that there was at least one positive blood donor in nine of these cases and that all ten recipients seroconverted during their illnesses. About 80 percent of chronic, post-transfusion NANBH (PT-NANBH) patients from Italy and Japan had circulating HCV antibody; a much lower frequency (15 percent) was observed in acute, resolving infections. In addition, 58 percent of NANBH patients from the United States with no identifiable source of parenteral exposure to the virus were also positive for HCV antibody. These data indicate that HCV is a major cause of NANBH throughout the world.