Genetic variants of hepatitis B virus in primary donors in Astana, Kazakhstan
The prevalence of one of the hepatotropic virus, hepatitis B virus (HBV) remains a serious global health problem. Since hepatitis B is transmitted through contact with blood or other fluids of an infected person, blood safety is one of the major public health issues in regions with high virus prevalence. Observed in recent years the trend to a shift in the prevalence of various genotypes of HBV in different geographical areas due to immigration from regions of the world with a high incidence of hepatotropic viruses, makes doctors and epidemiologists to pay close attention to the epidemiological situation in neighboring countries. The aim of our work was to study the characteristics of the genetic structure of the HBV in primary donors in Astana, Kazakhstan. A total of 30 blood plasma samples from newly diagnosed hepatitis B (HBsAg+) of Astana. HBV DNA was detected in 27 samples out of 30. Based on the phylogenetic analysis of the isolates showed that among patients examined HBV identified mainly D genotype, which is the most common genotype of HBV in Central Asia. Thus HBV subtype predominant D1 (85,2%) compared to the HBV subtype D2 (3,7%) and subtype D3 (7,4%), in a single sample was detected HBV genotypes A subtype A1. High similarities identified isolates previously described in Iran, Sudan, Mongolia, Tunisia suggest numerous independent, perhaps mutual, the importation of the virus in the country, including in the major migration waves. First detected at the territory of Kazakhstan HBV subtype A1, uncharacteristic for the region, as well as subtypes D2 and D3, which have a high similarity with the nucleotide sequences of HBV in Russia, show cases of importation of the virus from other countries. Identification of the propagation and the role of «imported» genotypes of HBV virus in circulation may be essential for regions where the prevalence of hepatotropic viruses is high, and the genome structure and the way of their distribution sufficiently studied.