Regional distribution of hepatitis C virus infection in the Republic of Korea, 2007-2011

Background/Aims: In Korea, hepatitis C is included as an infectious disease in a sentinel surveillance system. Recently, a large variation in hepatitis C incidence between different regions in Korea has been noticed. The current study verified the nationwide distribution of hepatitis C infection for effective prevention and management. Methods: We counted the number of hepatitis C patients who visited a hospital per county using the National Health Insurance database from 2007 to 2011. The age-adjusted prevalence ratio was used, and the age adjustment method was used as an indirect standardization method. Disease mapping and spatial analysis were conducted using a geographic information system. Results: The annual prevalence of diagnosed hepatitis C was approximately 0.12% to 0.13% in Korea. The age-adjusted prevalence ratios in Busan, Jeonnam, and Gyeongnam were high (1.75, 1.4, and 1.3, respectively). The three regions in the southern coastal area of the Korean Peninsula were identified as a high-prevalence cluster (Moran's index, 0.3636). Conclusions: The present study showed that hepatitis C infection has very large regional variation, and there are several high-risk areas. Preventive measures focusing on these areas should be applied to block the transmission of hepatitis C and reduce the disease burden.