Determination of Avian Influenza a Viruses in Some Avian Species in Van Lake Basin by Real Time-Pcr, Isolation and Subtyping

Abstract

In this study, feces samples collected during 37 months from February 2006 to March 2009 from 2013 animals consisting of 47 avian species covering irregular vagrant, transit migrant, winter visitor, migratory and native birds in the Van Lake Basin Turkey were tested by Real-Time PCR (RT-PCR) with respect to Avian Influenza (AI) type A virus M2 gene. Of them, 59 samples (2.9%) were found to be positive. RT-PCR positive samples were examined with the same method with respect to H5N1 and 4 samples (6.8%) were found to be positive. RT-PCR positive 59 samples were inoculated in Embryonated Chicken Egg (ECE) and AI type A virus was isolated from 12 samples (20.3%). Of the isolates, 3 were typed as H1N7, 2 as H7N9, 2 as H11N9 and 1 as H8N4 with Hemagglutination Inhibition (HI) and Neuraminidase Inhibition (NI) tests. About 4 isolates obtained from winter visitor Anas cylpeata which had been determined as H5N1 by RT-PCR and agarose gel electrophoresis, gave positive reaction by HI test both with HI and H5 antisera and all were typed as Nl by Nl-test. Feces samples found to be positive by RT-PCR belonged to avian species Anseriformes, Charadriiformes, Pas seriformes, Gruiformes and Phoenicopteriformes orders. The highest positivity was determined in winter visitor Anas acuta (37.1%) and Anas penelope (22.5%) ducks. Of the RT-PCR positive 59 samples, 43 (72.9%) were determined in the samples collected during winter and spring of 2006-2009. Positivity was determined at a rate of 35.2% in respect of AI type A by RT-PCR in different species sharing the same time and place. With this study, the presence of AI type A viruses in various wild birds in the Van Lake Basin was determined for the first time in Turkey. © Medwell Journals, 2011.