Current situation and trends in the hepatitis C virus genotype distribution among injecting drug users in the Czech Republic.

STUDY OBJECTIVES: To map the current distribution of hepatitis C virus genotypes among injecting drug users (IDUs) in the Czech Republic and to compare the results with the previously reported data. MATERIAL AND METHODS: Of 766 injecting drug users (IDUs) tested in the Remedis hepatology centre, Prague, in 2005 - 2007, 459 (60%) were anti-HCV positive, with viral replication detected by PCR in 326 (71%) of seropositives. PCR products from a randomly selected representative sample of 222 patients were analyzed by sequencing the NS5B region to determine HCV genotypes. Demographic and epidemiological data of the probands were collected by means of an interviewer-assisted questionnare survey. RESULTS: Of 222 study subjects, mostly long-term IDUs, including 154 (69%) males, mean age of 27 years, 131 (61%) reported opiates and 74 (35%) metamphetamine as their favourite drugs. Genotypic analysis found genotype 1, the most common one, in 168 (75.5%) subjects, with slight predominance of subtype 1a, detected in 90 (40.5%) subjects, over subtype 1b, identified in 78 (35%) subjects, while genotype 3 was revealed in 52 (23.5%) IDUs and showed a significant increase in 2007 compared to 2006. The comparison with the control data obtained 5 years earlier showed a substantial rise in the prevalence of genotype 3, previously rare in Czech IDUs, and a significantly increased proportion of subtype 1a among genotype 1 strains. Other genotypes reported from other European countries remain rare in the Czech Republic. CONCLUSIONS: Significant changes were found in the distribution and dynamics of HCV genotypes in the Czech Republic over the last years that are consistent with the changing route of HCV transmission in which injecting drug use currently plays the major role.