ABSTRACT
Newcastle disease virus (NDV, Avian orthoavulavirus type 1, AOAV-1) is a contagious high-impact poultry pathogen with infections detected worldwide. In the present study, 19,500 clinical samples from wild bird species and poultry collected from 28 regions of Russia between 2017 and 2021 were screened for the presence of the AOAV-1 genome. NDV RNA was detected in 15 samples from wild birds and 63 samples from poultry. All isolates were screened for a partial sequence of the fusion (F) gene that included the cleavage site. Phylogenetic analysis demonstrated that lentogenic AOAV-1 I.1.1, I.1.2.1, and II genotypes were dominant among vaccine-like viruses in the territory of the Russian Federation. A vaccine-like virus with a mutated cleavage site (112-RKQGR^L-117) was detected in turkeys. Among the virulent AOAV-1 strains, viruses of the XXI.1.1, VII.1.1, and VII.2 genotypes were identified. The cleavage site of viruses of the XXI.1.1 genotype had a 112-KRQKR^F-117 amino acid sequence. The cleavage site of viruses with VII.1.1 and VII.2 genotypes had a 112-RRQKR^F-117 amino acid sequence. The data collected by the present study demonstrate the distribution and dominance of the virulent VII.1.1 genotype in the Russian Federation between 2017 and 2021.
ABSTRACT
In April 2008 an avian influenza outbreak was diagnosed in Primorsky Krai, Russia, during the spring migration of wild birds, and A/Chicken/Primorsky/85/08 H5N1 isolate was recovered. The virus had more than 99% genetic identity with A/Whooper Swan/Hokkaido/1/08 H5N1 and A/Whooper Swan/Hokkaido/2/08 H5N1 viruses that were isolated in April 2008 in Japan. The amino acid sequence of the hemagglutinin cleavage site (PQRERRRKRGLF) and intravenous pathotyping index value (IVPI 2.80) were determined; on this basis the virus was characterized as highly pathogenic. The hemagglutinin gene of the virus was shown to belong to clade 2.3.2 while other genes (PB1, PB2, PA, NP, NA, M, NS) were characteristic of Fujian-like sublineage, recovered in the territory of Russia for the first time.