Submitted to: Options for the Control of Influenza Conference
Publication Type: Abstract Only
Publication Acceptance Date: 8/4/2013
Publication Date: 9/4/2013
Citation: Muzyka, D., Pantin Jackwood, M.J., Stegniy, B., Rula, O., Stegniy, A., Gerilovych, A. 2013. Monitoring of avian influenza viruses subtypes H5 and H7 in wild birds in the Azov-Black Sea region [abstract]. Options for the Control of Influenza VIII conference, September 4-10, 2013, Cape Town, South Africa. p. 15. Interpretive Summary:
Technical Abstract: Introduction. To date, influenza remains an unpredictable infection for animals, birds and people. The constant emergence of new strains and variants with new properties and pathogenicity for new hosts requires constant monitoring and careful research of new viruses. Since the main and primary reservoir of influenza viruses in nature is wild birds, especially waterfowl and shorebirds, constant epizootological monitoring in populations of these birds is necessary. The National Scientific Center "Institute of Experimental and Clinical Veterinary Medicine" in Ukraine, since 2000 conducts monitoring for influenza viruses in wild waterfowl and shorebirds in the Azov-Black Sea region of Ukraine. Particular attention was paid to the circulation of avian influenza viruses of subtypes H5 and H7, which can potentially be devastating to poultry. Materials and methods. Sampling of wild birds was conducted in the Azov-Black Sea region of Ukraine. This is the most important region of Eastern Europe from the ornithological point of view, since it’s in the cross of lines of flight of birds from the Baltic and Caspian seas to the Black and Mediterranean Seas, and from Western Siberia and Kazakhstan to Western Europe and North Africa. During the period from 2000 to 2011, biological material (cloacal, tracheal swabs, fecal samples) was collected from more than 6000 wild birds of 66 species orders Anseriformes and Charadriiformes. Virological investigations were carried out by standard methods recommended by the OIE. Results. During the period of 2005-2008 highly pathogenic avian influenza (HPAI) virus subtype H5N1 was detected from wild birds. Five viruses were isolated from great cormorants in 2006 and 3 viruses were isolated from a Great Grebe in 2008. These viruses belong to HA clades 2.2 and 2.2.3. originating from Asia, and Western Europe respectively. For the period from 2010 to 2012 during the large-scale monitoring studies of wild birds of different ecological groups, 59 influenza viruses of different subtypes were isolated, including a low pathogenic avian influenza (LPAI) virus subtype H5N2 which had a sequence similar to this subtype viruses that circulated in Europe in 2002. With regard to avian influenza virus subtype H7, no viruses were isolated during the 2000-2003 period, although antibodies to influenza virus H7 were detected in serum and egg yolks from some wild ducks. In the period of 2010-2012, seven H7 subtype viruses with different neuraminidase (H7N3, H7N6, H7N7) were isolated, representing 11.86% of the total number of influenza viruses collected during this time. All viruses of subtypes H5 and H7 were isolated from the wild Mallards during their autumn migration and wintering in the Azov-Black Sea region. These viruses did not cause disease in chickens after intranasal and intramuscular inoculation. Conclusions. The results indicate circulation of low pathogenic avian influenza viruses subtype H5 and H7 in wild waterfowl populations in the Azov-Black Sea region. These findings support the need for ongoing monitoring of avian influenza for early prevention of highly pathogenic variants of viruses that may pose a threat to poultry.