[Studies of properties of pandemic influenza virus A/H1N1 circulated in Russian Federation in 2009 - 2010].

AIM: Studies of cultural, virologic, antigenic properties of 89 samples of pandemic influenza A(H1N1) 2009 virus isolated in Russian Federation from May 2009 to March 2010. MATERIALS AND METHODS: Properties of isolated samples were compared with those of the reference strain A/ California/04/2009 (H1N1). RESULTS: Studies of biological properties and analysis of genome nucleotide sequences of the isolated samples showed that those strains are closely related to the reference strain. CONCLUSION: Monitoring of genetic, virologic and antigenic properties of pandemic influenza A(H1N1) 2009 virus isolates carried out from May 2009 to March 2010 did not reveal significant changes in the abovementioned properties of the virus or emergence of mutations that can lead to such changes.

[Genetic variability of isolates of pandemic influenza A virus H1N1 isolated in Russia in 2009].

Complete nucleotide sequence of the genome segments encoding the surface glycoproteins, hemagglutinin, and neuraminidase of influenza A virus H1N1 derived from the patients with influenza in the context of pandemic (H1N1) 2009 was determined out of 14 isolates of pandemic influenza. The philogenetic analysis of these sequences demonstrated their genetic similarity to the corresponding genes of the pandemic influenza virus A (H1N1) 2009 isolates obtained in other countries; each gene homology was greater than 99%. Neuraminidase mutations causing virus resistance to oseltamivir and other neuraminidase inhibitors, known from the literature, were not detected. The hemagglutinin gene mutation D222G was found in 4 isolates from autopsy material. In the hemagglutinin of pandemic A/Salekhard/01/2009(H1N1) isolate a mutation G155E leading to the increase in viral replication in developing chick embryos was detected. The nature and frequency of nucleotides substitutions within HA and NA genes were determined in the current research.