[Experimental infection caused by influenza A (H5N1) virus in common gull (Larus canus)].

The influenza A/common gull/Chany/P/2006 (HSN1) virus strain Isolated from a clinically healthy common gull (Larus canus) caused no death of Its natural host (a common gull). The virus was shown to be capable for effective replication in the tissues of the lung, spleen, and upper respiratory tract and in the intestinal mucosal cells of the common gull with further environmental virus liberation elimination along with mucinous discharges from the cloaca and fauces for 2 weeks. The potential role of this bird species in the circulation of influenza virus is discussed.

[Characteristic of high pathogenic avian influenza virus subtype H5N1 isolated from common gull (Larus canus)].

AIM: To study biological characteristics of H5N1 influenza virus isolated from common gull on south of West Siberia in 2006. MATERIALS AND METHODS: Isolation and characterization of biological characteristics performed according to recommendations of World Health Organization. RESULTS: Influenza virus A (H5N1) was first isolated from common gull (Larus canus) in Russia. Antigen of isolated virus had significant affinity to polyclonal sera obtained against high pathogenic avian influenza viruses H5N1 circulating in South-East Asia. Phylogenetic analysis of isolated strain revealed its belonging to group of Qinghai-related variants of H5N1 influenza virus. Aminoacid structure of hemagglutinin proteolytic cleavage site is characteristic for type A high pathogenicity avian influenza viruses. Experimental infection of chickens demonstrated high pathogenicity of the isolated virus. CONCLUSION: Involvement of common gulls in circulation of subtype H5N1 influenza virus is demonstrated for the first time. Important role of species from Laridae family in unprecedented spreading of H5N1 influenza virus started in 2005 is discussed.

[Results of two-year-old inspection of the presence of infuenza virus in wild birds in Western Mongolia].

The results of virology inspection of the wild birds living in territory of the Western Mongolia, carried out in 2003-2004 are presented. For the specified period influenza viruses H3 and H4 subtype hemagglutinins are isolated from birds. It is revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given territory. Influenza viruses are isolated from birds of 5 special groups; among them there are preferring water and nearwater biotops, a species preferring dry plain region, and also a species which habitat does not depend from water's territories.

[Study of highly pathogenic H5N1 influenza virus isolated from sick and dead birds in Western Siberia].

The mass destruction of domestic birds has been registered in July, 2005 in Novosibirsk region. Influenza virus H5N1 have been isolated from bodies of the lost birds on developing chicken embryos and identified by serological and molecular biological methods. M-gene and genes coding hemagglutinin and neurominidase were in part sequening. The phylogenetic analysis of hemagglutinin gene has shown, that the isolated viruses are forming a claster with strains, isolated from birds during outbreak of the bird's flu on lake Tsinghai (Qinghai) in China in 2005, in Japan in 2004, and also with H5N1 strains, isolated from the person and birds in the countries of Southeast Asia during ipizootia in 2003-2004. The site of the restriction which associated with pathogenicity of isolated avian influenza viruses H5 serogroup, corresponds to sequence of high pathogenic strains, circulating in the countries of Southeast Asia. The test for pathogenicity with use of chickens has confirmed, that researched strains were high pathogenic for birds.

[West Nile virus genotyping among wild birds belonging to ground and tree-brush bird populations on the territories of the Baraba forest-steppe and Kulunda steppe (2003-2004)].

The paper gives the results of the 2003-2004 examinations of 104 wild birds belonging to land tree-brush complexes from the Baraba forest-steppe and Kulunda steppe for the detection and genotyping West Nile virus (WNV). ELISA and RT-PCR were used to show that in the forest-steppe and steppe zones of the south of Western Siberia, WNV circulates among both migrating and settled birds. An analysis of the nucleotide sequence of a protein E gene fragment showed the circulation of WNV genotype Ia in the study birds. A number of revealed amino acid substitutions in surface glycoprotein E are unique for the 2003-2004 Western-Siberian WNV variants and absent in the 2002 Western-Siberian variants, which suggests that there are regional features of the evolution of WNV genotype Ia.

[The 2003 results of monitoring of influenza A virus in the populations of wild birds in the south of Western Siberia].

The paper presents the results of isolation of influenza A virus from 97 cloacal swabs of 11 species of aquatic and semiaquatic wild birds collected on the Chany Lake (the south of Western Siberia, Ob-Irtysh interarea). Six strains with subtypes H2 (2 strains), H3 (3 strains), and H5 (1 strain) were isolated from mallard ducks (Anas platyrhynchos). The total infection rate in the examined birds was 6.2% and that in the ducks was 9.7%. The paper deals with the phylogenetic analysis of hemagglutinin of genes of isolates and with the comparison of the obtained results with the 2002 data in the same region. Analysis of H5 strain hemagglutinin proteolytic site permits one to regard this strain as non-pathogenic.

[Genetic variety of influenza A virus in the populations of wild birds in the south of Western Siberia].

Influenza A virus variants belonging to H3 and H4 subtypes were isolated from wild ducks inhabiting in the south of Western Siberia. Phylogenetic analysis of hemagglutinin (HA) gene of these viruses has revealed that H3 isolates are closely related to those isolated from the bird inhabiting in West Europe (A/Teal/Germany/wv01r/01, A/Duck/Ukraine/1/63) and China (A/Aquatic bird/Hong Kong/399/99); and those isolated from the birds inhabiting in Germany (A/Garganey/Germany/wv157k/01, A/Teal/Germany/wv153k/01). Thus, closely related influenza A virus variants circulate in the populations of the wild birds inhabiting in greatly spaced regions of Eurasia.