HCV Genotype and Subtype Distribution of Patient Samples Tested at University of Texas Medical Branch in Galveston, Texas

Six genotypes of Hepatitis C Virus (HCV), each comprising multiple subtypes have been identified worldwide. Substantial regional differences appear to exist in the distribution of HCV genotypes and subtypes. The HCV genotype variability accounts for the responses to treatments and clinical outcomes and HCV genotyping is standard of care for viral hepatitis C management. The aim of this study was to determine the distribution of HCV geno/subtypes routinely generated in the Molecular Diagnostics Laboratory at the University of Texas Medical Branch (UTMB) in Galveston, Texas. Analysis of the HCV geno/subtype results from 1,318 patients between September 2007 and February 2009 revealed subtype 1a was the most frequent, identified in 828 (62.8%) specimens. Subtypes 3a, 1b, 2b, 4, 6 and 3b were identified in 163 (12.4%), 144 (10.9%), 110 (8.2%), 7 (0.5%), 2 (0.2%) and 1 (0.1%) samples, respectively. Cases of mixed infection were rarely identified (1.4%).