MOLECULAR EPIDEMIOLOGY FEATURES OF HEPATITIS C VIRUS ISOLATES FROM DIFFERENT REGIONS OF THE REPUBLIC SAKHA (YAKUTIA)

Abstract

According to WHO data about 3% of population are infected by hepatitic C virus (HCV) worldwide. Chronic hepatitis C is the leading cause of cirrhosis and hepatocellular carcinoma, thus it becoming one of the global public health problems. Clinical manifestations are varied and depend mainly of the virus biological properties and its interaction with the host immune system. Determination of virus genotype and subtype is important for a better understanding of the epidemiological and virological features of the disease. The prevalence genotypes hepatitis C virus is varies in different geographical regions of the world. The data about HCV genotypes distribution in some Russian Federation regions are very limited, especially about HCV genotypes prevalence in Siberia, Far East and some rural regions. One of such regions is Yakutia. In our study we identified genetic variants of HCV in chronic hepatitis C patients with moderate and high viral load from Yakutia by direct sequencing of HCV RNA NS5B region. Based on phylogenetic analysis we found the prevalent genotype 1 (88.3%), than genotype 2 (6.7%) and 3 (3.2%) among HCV patients with moderate and high viral load. Our results on the prevalence of subtype 1b are consistent with the data on the connection between this subtype with high levels of viremia, greater duration and severity of liver disease, as well as the development of chronic hepatits C in patients infected by HCV subtype 1b, compared with those infected with other subtypes of hepatitis virus C. The similarity of some Yakutian isolates with isolates from the United States, Brazil and Ireland was found. We discuss HCV subtype 2a isolates identified origin from isolates found in China. First in the territory of the Russian Federation HCV subtype 3g was identified, presumably imported from South Asia. Interconnected use of molecular, virological, demographic and epidemiological methods and information to monitor the infections will contribute to the understanding of the current HCV epidemiology in Russia.