RESUMO
The results of the biological property investigation of two Newcastle virus strains isolated in Northern Caucasian region--NDV/Adigeya/duck/8/2008 and NDV/Adigeya/duck/15/2008--were presented. The phylogenetic analysis revealed that these strains belonged to genotype 7 of clade 2. Using molecular-biological analysis of established nucleotide sequences including proteolytic site of fusion peptide it was demonstrated that the strains were velogenic. This conclusion was proved by testing the pathogenicity on the model of intracerebral infected chickens (ICPI--IntraCerebral Pathogenic Index--was found to be 2). Pathomorphological study of dead chickens made it possible to classify strains as neurotropic with low level of visceral tropism.
Assuntos
Doença de Newcastle/virologia , Vírus da Doença de Newcastle , Proteínas Virais/genética , Tropismo Viral/genética , Animais , Embrião de Galinha , Galinhas , Feminino , Genótipo , Masculino , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/isolamento & purificação , Vírus da Doença de Newcastle/patogenicidade , Federação RussaRESUMO
AIM: Study of molecular-biological and antigenic features of H5N1 subtype virus strains isolated in southern Siberia in 2005-2009. MATERIALS AND METHODS: Study was performed by using standard procedures according to WHO recommendations. RESULTS: Hemagglutinin gene of H5N1 subtype virus strain isolated in Siberia belongs to 2 genetical lineages: 2.2 and 2.3.2. Strains of these 2 lineages have antigenic differences. All of the strains are highly pathogenic for chicken and white mice. CONCLUSION: H5N1 subtype highly pathogenic influenza virus variants of 2 different antigenic lineages that have antigenic differences circulated in Siberia in 2005-2009. A possible role of antigenic drift in evolution of H5N1 subtype influenza virus is discussed.
Assuntos
Antígenos Virais/genética , Hemaglutininas Virais/genética , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Animais , Aves/virologia , Galinhas/virologia , Humanos , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Sibéria/epidemiologiaRESUMO
The study of basic biological properties of H5N1 subtype strain isolated during an outbreak among wild birds in Russia in 2010 was presented. The study was carried out using conventional methods according to the WHO recommendations. H5N1 influenza virus isolated in Siberia belonged to clade 2.3.2 of the hemagglutinin gene; the phylogenetic analysis was performed. The antigenic characteristics and the basic genetic markers of biological properties were studied. It was shown that all strains were highly pathogenic for chickens and white mice. Thus, it was shown that in Russia in the 2010 H5N1 virus phylogenetically closely related to Asian variants caused epizootic among wild birds. The potential danger of this variant of the virus for humans was confirmed by different methods. We discussed the possibility of formation of H5N1 influenza natural focus.