Risk factors for hepatitis C virus infection among Koreans according to the hepatitis C virus genotype.

To investigate risk factors for HCV infection according to the genotype, we studied 178 patients positive for HCV-PCR and 226 controls that were negative for the anti-HCV antibody. One hundred and twenty five controls (community control) were recruited from spouses of HCV-PCR-positive patients and the other 101 from hospital visitors (hospital control). HCV genotyping was performed by PCR, and epidemiological data were obtained from all participants. The distribution of HCV genotypes was as follows -- 1a (0.6%), 1b (39.9%), 2a (38.2%), 2b (0%), 3 (1.1%), and unclassified (20.2%). By multivariate analysis, blood transfusion (OR 2.90) and endoscopy (OR 2.80) were found to be risk factors for HCV genotype 1b versus the community control. Similarly, blood transfusion (OR 3.17) was found to be risk factors for HCV genotype 1b versus the hospital control. Blood transfusion (OR 2.75) and endoscopy (OR 3.57) were risk factors for HCV genotype 2a versus the community control, and blood transfusion (OR 4.55) and endoscopy (OR 2.16) were those versus the hospital control. Our results suggest that the risk factors for HCV infection are similar among the different genotypes. Blood transfusion and endoscopy were found to be associated with HCV infection.