Hepatitis C virus genotyping in Greece: unexpected high prevalence of genotype 5a in a Greek island.

Hepatitis C virus (HCV) genotype 5 (G5) is a rare genotype reported mainly in South Africa. However, increasing data suggest the sporadic presence of this genotype in different European countries. To assess the epidemiology of HCV-G5 in Greece, genotyping was performed in 973 consecutive patients infected with HCV, referred to 7 hepatology centers throughout Greece, from January 2005 to December 2009. Genotype 5a (19 patients, 1.9%) was the fifth most prevalent genotype after genotype 1 (408 patients, 41.9%), genotype 3 (318 patients, 32.7%), genotype 4 (158 patients, 16.2%), and genotype 2 (70 patients, 7.2%). The majority of patients infected with G5 (16/19,84.2%) were referred to the General Hospital of Rhodes, an island in south-east Greece. The HCV genotype distribution in that particular island, indicates a particularly high G5 prevalence of 12.8%, after genotype 1 (40%), genotype 3 (28%), and genotype 4 (15%). Among the patients from Rhodes infected with G5 (n = 16), 13 (81.2%) were females. The mean age was 62.3 ± 6.5 years, significantly older than the patients infected with other HCV genotypes (mean age 40.6 ± 7.2, P < 0.0001). Nine out of the 16 cases (56.2%) presented features of high pre-treatment viral loads. Advanced liver fibrosis (Metavir F3-F4) was found in four out of five performed liver biopsies. Ten patients received treatment with pegylated interferon plus ribavirin and a sustained viral response were achieved in six cases. The source of infection is unknown but parenteral iatrogenic routes of transmission seem to have contributed significantly to the spread of genotype 5a in this region.