Genotypic analysis of HCV infection in Kinmen

In this report, stratified random sampling of an epidemiological study population from the town of Kin-Hu in the Kinmen Islands was used to create a subpopulation of 832 individuals. Two enzyme immunoassays (EIA) were used for antibody testing including Abbott's hepatitis C virus (HCV) EIA 2nd Generation and a synthetic peptide-EIA, NANBASE C-96-EIA, based on the locally predominant strain of HCV. In addition to RIBA and DBL immunoblot assays, reverse transcription-polymerase chain reaction (RT-PCR) was employed to confirm HCV infection. Results showed that 20 of 832 (2.4%) adults in Kinmen had HCV infection. In terms of genotype distribution, 31.3% (5/16) were infected with both 1a and 1 b genotypes, 25.0% (4/16) only with the 1b genotype, and 43.8% (7/16) with the 2a genotype. Through comparative analysis of RT-PCR, RIBA, and DBL results, we found that the sensitivities of RIBA and DBL could safely be increased by modifying the definition of a positive case. If the presence of a reactive band with ≥ 2+ antibody reactivity to core protein is accepted as positive for overall RIBA or DBL testing, sensitivity is increased without adversely effecting specificity.