Antibody to Hepatitis C Virus in Risk Groups in Canada

Abstract

The prevalence of antibodies against hepatitis C virus (HCV) was studied in hemophiliacs, hemodialysis patients, intravenous drug abusers, female prisoners, homosexuals, individuals with no markers of recent hepatitis A or B virus infections and normal individuals (federal public servants), by an enzyme immunoassay (Ortho Diagnostic Systems Inc). Repeat positive samples were further tested by recombinant immunoblot assay (RIBA) HCV (Chiron Corp, California). The number of samples positive for antibodies to HCV (anti-HCV) was higher with enzyme immunoassay than byRIBAHCV in most cases. A high prevalence of anti-HCV was detected in hemophiliacs by both enzyme immunoassay (68.8%) andRIBAHCV (53.7%). Among intravenous drug abusers and female prisoners the prevalence rates for anti-HCV were 42.8% and 29.8%, respectively, byRIBAHCV; the results with enzyme immunoassay were only slightly higher. The prevalence rate was also high by both tests (54.2%) in hemodialysis patients’ sera taken during 1980–82, when many cases of non-A,non-B hepatitis were suspected in this group. In contrast, only 14.1% of sera taken during 1990 were positive byRIBAHCV. In individuals with no markers of recent hepatitis A or B infections, 13.4% were positive by enzyme immunoassay, whereas only 4.5% were reactive byRIBAHCV. The lowest prevalence was seen in homosexuals (2.3%) and normal individuals (1.2%) byRIBAHCV. These results indicate a high prevalence of anti-HCV in high risk groups tested in Canada.