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Monitoring programs for highly dangerous avian diseases in the Russian Federation from 2001 to 2009 detected 77 samples that were PCR positive for avian paramyxovirus serotype-1 (APMV-1) from sick or dead feral and domestic pigeons. Nucleotide sequences of the fusion (F) gene, including a nucleotide sequence encoding the F protein cleavage site, were determined for these isolates. All of the studied isolates possessed virulent F0 protein cleavage sites (112KRKKRF117, 112RRQKRF117, or 112KRQKRF117). Intracerebral pathogenicity index (ICPI) values determined for seven of the isolates exceeded the value of 0.7 (the range from 0.8 to 1.41). Based on partial genome sequencing and phylogenetic analysis, the isolates were assigned to two individual sublineages within class II genotype VIb. It was determined that most of these Newcastle disease virus isolates (70/77) recovered from the pigeons belonged to a relatively poorly studied sublineage VIb/2. The complete nucleotide sequence of the genome for the Pigeon/Russia/Vladimir/687/05 isolate of sublineage VIb/2 was determined.

The F gene fragment of 79 Newcastle disease virus (NDV) strains isolated from domestic and synanthropic birds in Kazakhstan, Kirghizia, Ukraine, and Russia in 1993 to 2007 was comparatively analyzed. Phylogenetic analysis of test isolates and reference NDV strains obtained from the GenBank was carried out by polymerase chain reaction with subsequent sequencing and comparative analysis of 154-bp nucleotide sequences in the main functional region of the F gene. All newly characterized isolates belong to three NDV genotype VII subgroups: VIIa, VIIb, VIId. The results show it necessary to monitor of NDV strains isolated in the CIS countries since the spread of NDV among migratory and synanthropic birds (pigeons, crows, and jackdaws) poses a serious threat to commercial poultry industry.

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.

A field isolate of Newcastle disease virus (NDV) was isolated in the Russko-Vysotskaya poultry farm, Leningrad region. Within four days after infection, the isolate caused 100% mortality in 60-day-old susceptible chickens. The HA titer of the allantoic fluid samples collected after one passage in SPF-chicken embryos was 1:512, and it reacted only with the NDV specific antiserum in HI test. Intracerebral pathogenicity index and mean embryo death time were 1.97 and 49 hours, respectively. The isolate has the amino acid sequence of the protease cleavage site of the fusion protein F0 (112R-R-Q-R-R-F117), which is similar to that in the velogenic strains of NDV. Therefore, it was concluded that the virus isolated in this work was an ethiological agent of the ND outbreak in this poultry farm.