GENOTYPING OF HEPATITIS-C VIRUS ISOLATES FROM BASQUE COUNTRY, SPAIN

The genotype of HCV was determined in 161 chronic HCV-infected patient s. The patients were classified into three groups on the basis of the origin of the HCV infection: 50 patients had a history of intravenous drug use (IVDU) but no HIV infection; 41 patients had received blood t ransfusions, and 70 patients had no known exposure. The distribution o f HCV genotypes was associated with the origin of infection and age of patients: genotype Ib was predominant among patients who had received blood transfusions and those without evidence of parenteral exposure (84.6% and 67.7%, respectively), whereas genotype 3a was present in 65 .3% of IVDUs. Patients with genotype 1b were older than those with gen otypes 1a or 3a: 50.3 +/- 12 vs. 34.1 +/- 9.9 and 31 +/- 5.4 years, re spectively. These findings suggest that the pattern of HCV genotypes i n our region is changing and that genotype 1b may be substituted by 3a as the dominant genotype in the future.