[Molecular analysis of an avian influenza virus isolate of H5N2 subtype from parrot]

In 2005, an avian influenza virus stain was isolated from Parrot in Guangdong, which was then genotyped as H5N2 subtype and designated as A/Parrot/Guangdong/268/2005. According to the current OIE definition on the low-pathogenicity of avian influenza virus, the strain was recognized as a low pathogenic avian influenza virus due to the presence of one basic amino acid residue at the HA cleavage site. Some molecular characteristics of the virus, such as potential glycosylation sites in HA and NA, receptor binding sites of HA, and drug resistance site of NA, showed no variations. To analyze molecular evolution of this strain, we selected the sequences of H5N2 subtype AIVs from GenBank and established the phylogenetic trees. Our results indicated that this strain shared the highest homologies with the H5N2 LPAI isolate A/Pheasant/NJ/1355/1998-like. Phylogenic analysis revealed the isolate, together with A/Chicken/Pennsylvania/1/1983 (H5N2), belonged to America lineages and clustered with A/Pheasant/NJ/1355/1998-like.