Community and personal risk factors for hepatitis C virus infection: A survey of 23 820 residents in Taiwan in 1991-2

Aim: The aim of this study was to explore the community-level risk factors, such as high hepatitis C viruse (HCV)-RNA positive rate and limited medical resources in a township, for HCV infection, one major cause of liver cirrhosis and hepatocellular carcinoma. Methods: This study enrolled 23 820 residents living in 155 villages of seven townships in Taiwan in 1991-2 to explore both individual and community risk factors for HCV infection. Antibodies against HCV (anti-HCV), HCV-RNA and HCV genotype in serum samples were determined by enzyme immunoassay, PCR and melting curve analysis, respectively. Results: The overall anti-HCV seroprevalence was 5.5%, HCV-RNA was detectable in 68.1% of the seropositives of anti-HCV, and genotype 1 was the most prevalent genotype (54.6%). Personal risk factors for the seropositivity of anti-HCV included older age, female gender, low educational level and history of blood transfusion. Based on the multilevel analysis, persons living in villages with high HCV-RNA-positive rates and limited healthcare resources had an increased seroprevalence of anti-HCV after adjustment for individual risk factors. The multivariate-adjusted prevalence OR (95% CI) was 3.49 (1.80 to 6.76) and 8.48 (5.07 to 14.20) for villages with medium and high HCV-RNA positive rate, respectively. The multivariate-adjusted OR (95% CI) was was 1.75 (0.76 to 4.01) and 3.91 (2.25 to 6.80), respectively, for villages with medium and poor healthcare resources. Conclusions: This study suggests that community risk factors contribute significantly to the variation in anti-HCV seroprevalence. It implies both the adequacy of healthcare resources and the treatment of patients positive for HCV-RNA may prevent individual residents from the acquisition of HCV infection from the community.