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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Exotic & Emerging Avian Viral Diseases Research » Research » Publications at this Location » Publication #347911

Research Project: Intervention Strategies to Prevent and Control Disease Outbreaks Caused by Emerging Strains of Avian Influenza Viruses

Location: Exotic & Emerging Avian Viral Diseases Research

Title: Continuing evolution of H9N2 avian influenza virus in South Korea

Author
item Youk, Sung-su - Orise Fellow
item Lee, Dong-hun - Orise Fellow
item Pantin-jackwood, Mary
item Kwon, Jung-hun - Konkuk University
item Lee, Sun-hak - Konkuk University
item Song, Chang-seon - Konkuk University
item Swayne, David

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/2/2018
Publication Date: 4/15/2018
Citation: Youk, S., Lee, D., Pantin Jackwood, M.J., Kwon, J., Lee, S., Song, C., Swayne, D.E. 2018. Continuing evolution of H9N2 avian influenza virus in South Korea. Abstract book for the 10th International Symposium on Avian Influenza in Brighton, United Kindom, April 15-18, 2018. Paper No. 126.

Interpretive Summary:

Technical Abstract: The H9N2 low pathogenic avian influenza (LPAI) has caused great economic losses in Korean poultry industry since the first outbreak in 1996. Although the hemagglutinin gene of early H9N2 viruses were closely related to Chinese Y439-like lineage virus, it evolved into a unique Korean lineage after some years of being endemic in domestic poultry. To better understand the genetic characteristics of the Korean H9N2 viruses, we focused on internal gene segments of H9N2 viruses from live bird markets. Among 110 avian influenza confirmed samples from 2006 to 2016, 75 isolates were identified as H9N2 virus. Full-length viral genome sequencing and phylogenetic analysis identified frequent internal gene reassortment with local LPAI viruses to produce several novel genotypes. We found evidence that H9N2 viruses isolated from live bird markets during 2006-2008 were natural reassortant viruses generated by genetic reassortment between the poultry origin H9N2 and wild bird origin H5N2 LPAI viruses. This event contributed to the diversity of H9N2 virus genotypes, and reassortants continued to evolve until 2016. In addition, several mammalian markers for avian influenza virus became constant in polymerase genes, which indicate that continuous surveillance is needed to monitor whether these viruses acquire higher pathogenicity and wider host range.