Molecular epidemiology of hepatitis C virus and its relation with persistence or clearance of infection in Hamadan, West-Iran

Hepatitis C Virus genotyping appears to be vital for predicting the response to antiviral therapy. The present study aimed to analyze the HCV genotypes in relation to persistence or clearance of the virus in residents of Hamadan Province, West-Iran. A total of 1159 recorded questionnaires of HCV infected people were evaluated in this prospective study. Several parameters including HCV genotypes, anti-HCV antibodies, viral load, drug treatment, response to therapy and amount of ALT and AST were analyzed. HCV genotyping in 637 samples revealed a predominance of type 1a (52.1%) followed by 3a (42.4%), type 1b (2.7%) and type 2 (0.2%) respectively. Mixed genotypes (3a-1a) were detected in 0.9%, and 1.7% had untypable genotype. High frequency of genotypes 1a and 3a were observed in drug-resistant (group-a) and drug-sensitive (group-b) patients respectively (P<0.0001). Additionally, duration of drug treatment was significantly higher in group-a than group-b (P<0.0001). During follow-up period, 92 cases showed spontaneous clearance of HCV infection and more importantly 86 of 92 cases were positive for anti-HCV antibodies compared with 59 of 455 antibody positive cases with treatment-induced clearance of HCV infection (P<0.0001). HCV genotyping and also antibody screening could be useful for proper therapeutic intervention in HCV infected subjects.