RESUMEN
Few studies are available on hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection in populations living in small and medium-sized Brazilian cities. We evaluated the seroprevalence of these viruses in selected individuals from a clinic of infectology, who were referred to the University Regional Hospital of the West Region of state of São Paulo, Brazil. Among a total of 7,021 individuals seen in the clinic following receipt of preliminary ELISA results or having the suggested clinical signs of viral hepatitis or HIV, 1,228 were systematically screened. Isolated or associated HBsAg, HCV and HIV antibodies were found in 44.9 percent of the subjects. Anti-HIV antibodies were found in 24.7 percent of the patients, 20.3 percent of whom had an HIV monoinfection and 4.4 percent of whom were co-infected with hepatitis viruses (HCV: 4 percent; HBV: 0.4 percent). Anti-HCV antibodies were found in 14 percent of the patients and 5.9 percent had anti-HBsAg antibodies. HCV infection affected males more than females (p < 0.05) and individuals > 50-years old had an increased prevalence of anti-HCV compared to HIV (p = 0.0001) or HBV (p = 0.0063). HCV-RNA was detected in 73.5 percent of the samples with a predominance of genotype 1 (72.5 percent). A significant percentage (44.9 percent) of the selected individuals was positive for antibodies against HBV, HCV and/or HIV; these patients would otherwise have remained undiagnosed.