Molecular epidemiology of hepatitis C virus strains from Romania.

BACKGROUND AND AIMS A high seroprevalence of Hepatitis C Virus (HCV) infection has been reported in Romania, with limited data on the viral subtypes' distribution. In order to detect any changes in the genetic composition of the epidemic, a survey on the recent profile of circulating HCV genotypes was conducted. METHODS 241 hepatitis C infected patients with active viral replication diagnosed between September 2004 - October 2008 were included in a retrospective study. Genotyping using commercial Line Probe Assay (Innogenetics) was confirmed by sequencing of Core PCR products followed by phylogenetic analysis. RESULTS HCV subtype 1b was found in 92.6% of the samples, subtype 1a in 5.4 % of the samples, subtype 4a in 1.2%, and subtype 3a in 0.8% of the samples. Chronic hepatitis C infections with subtype 1b were found in women aged 40-60 years old with a history of blood transfusions received during surgical/obstetrical interventions. No geographical clustering was evident for HCV 1b sequences. The new emerging non-1b genotypes were detected mainly in younger patients with a history of intravenous drug use. The genetic distances among the HCV 1a strains are very homogeneous and small, with a high sequence identity with other European strains, suggesting the recent entrance of this subtype in Romania from singular or limited sources of infection. CONCLUSION The introduction of new HCV genotypes in Romania stimulates a continuous epidemiological surveillance, suggesting shifts in the transmission pathways and risk factors, with the possible emergence of recombinant strains in patients with multiple infections.