Newcastle disease outbreaks in Kazakhstan and Kyrgystan during 1998, 2000, 2001, 2003, 2004 and 2005 were caused by viruses of the genotypes VIIb and VIId

Authors: BOGOYAVLENSKIY, A - Institute Of Microbiology And Virology; BEREZIN, V - INST MICROB, KAZAKHSTAN; PRILIPOV, A - INST VIROLOGY, RUSSIA; USACHEV, E - INST VIROLOGY, RUSSIA; LYAPINA, O - INST VIROLOGY, RUSSIA; KOROTETSKIY, I - INST MICROB, KAZAKHSTAN; ZAITCEVA, I - INST MICROB, KAZAKHSTAN; ASANOVA, S - INST MICROB, KAZAKHSTAN; KYDYRMANOV, A - INST MICROB, KAZAKHSTAN; DAULBAEVA, K - Institute Of Microbiology And Virology; SHAKHVOROSTOVA, L - INST MICROB, KAZAKHSTAN; SAYATOV, M - INST MICROB, KAZAKHSTAN; King, Daniel

Submitted to: Virus Genes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/7/2009
Publication Date: 5/23/2009
Citation: Bogoyavlenskiy, A., Berezin, V.E., Prilipov, A.G., Usachev, E.V., Lyapina, O.V., Korotetskiy, I.S., Zaitceva, I.A., Asanova, S.E., Kydyrmanov, A., Daulbaeva, K., Shakhvorostova, L.M., Sayatov, M.K., King, D.J. 2009. Newcastle disease outbreaks in Kazakhstan and Kyrgystan during 1998, 2000, 2001, 2003, 2004 and 2005 were caused by viruses of the genotypes VIIb and VIId. Virus Genes. 39:94-101.

Interpretive Summary: The diminished productivity of poultry flocks in most countries in the world is due in part to a continuing problem with Newcastle disease (ND). Newcastle disease virus (NDV) isolates from samples obtained from ND outbreaks that occurred in chickens in Kazakhstan and Kyrgystan during the period 1998 to 2005, were characterized to determine their virulence and sequence analysis of the virus genes was utilized to determine the genetic type of the virus and for comparison with the genetic sequence of viruses recovered in other parts of the world. Although some isolates were more virulent than others, all were of a virulence that would make the outbreaks notifiable events by World Organization of Animal Health standards. The virus genotypes of isolates recovered were found to be similar to those recovered in other countries. However, the isolates recovered during 1998-2001 differed genetically from those recovered during 2003-2005 and indicated that either a mutation occurred in viruses endemic to the region or that an introduction of new viruses had occurred. Knowledge of the virulence and genetic type of the NDV strains causing ND in these countries will be useful in developing diagnostic and control programs to reduce the impact of ND in these countries.

Technical Abstract: Newcastle disease virus (NDV) infects domesticated and wild birds throughout the world and infections with virulent NDV strains continue to cause disease outbreaks in poultry and wild birds. To assess the evolutionary characteristics of 28 NDV strains isolated from chickens in Kazakhstan and Kyrgyzstan during 1998, 2000, 2001, 2003, 2004 and 2005 we investigated the phylogenetic relationships among these viruses and viruses described previously. For genotyping, fusion (F) gene phylogenetic analysis (nucleotide number 47-421) was performed using sequences of Kazakhstanian and Kyrgystanian isolates as compared to sequences of selected NDV strains from GenBank. Phylogenetic analysis showed that 14 newly characterized strains from years 1998 to 2001 belonged to the genetic group designated as VIIb whereas the 14 strains isolated during 2003 to 2005 were of genotype VIId. All strains possessed a virulent fusion cleavage site (RRQRR/F) belonging to velogenic or mesogenic pathotypes with intracerebral pathogenicity indexes (ICPI) varying from 1.05 to 1.87.