[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]
BMC Infect Dis. 2019 May 22;19(1):458. doi: 10.1186/s12879-019-4079-z.
Genetic and biological characteristics of avian influenza virus subtype H1N8 in environments related to live poultry markets in China.
Zhang Y1, Dong J1, Bo H1, Dong L1, Zou S1, Li X1, Shu Y1,2, Wang D3.
Author information: 1 Chinese National Influenza Centre, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention; WHO Collaborating Center for Reference and Research on Influenza; Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing, China. 2 Present Address: Public Health School (Shenzhen), Sun Yat-sen University, Guangzhou, China. 3 Chinese National Influenza Centre, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention; WHO Collaborating Center for Reference and Research on Influenza; Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing, China. firstname.lastname@example.org.
Since 2008, avian influenza surveillance in poultry-related environments has been conducted annually in China. Samples have been collected from environments including live poultry markets, wild bird habitats, slaughterhouses, and poultry farms. Multiple subtypes of avian influenza virus have been identified based on environmental surveillance, and an H1N8 virus was isolated from the drinking water of a live poultry market.
Virus isolation was performed by inoculating influenza A-positive specimens into embryonated chicken eggs. Next-generation sequencing was used for whole-genome sequencing. A solid-phase binding assay was performed to test the virus receptor binding specificity. Trypsin dependence plaque formation assays and intravenous pathogenicity index tests were used to evaluate virus pathogenicity in vitro and in vivo, respectively. Different cell lines were chosen for comparison of virus replication capacity.
According to the phylogenetic trees, the whole gene segments of the virus named A/Environment/Fujian/85144/2014(H1N8) were of Eurasian lineage. The HA, NA, PB1, and M genes showed the highest homology with those of H1N8 or H1N2 subtype viruses isolated from local domestic ducks, while the PB2, PA, NP and NS genes showed high similarity with the genes of H7N9 viruses detected in 2017 and 2018 in the same province. This virus presented an avian receptor binding preference. The plaque formation assay showed that it was a trypsin-dependent virus. The intravenous pathogenicity index (IVPI) in chickens was 0.02. The growth kinetics of the A/Environment/Fujian/85144/2014(H1N8) virus in different cell lines were similar to those of a human-origin virus, A/Brisbane/59/2007(H1N1), but lower than those of the control avian-origin and swine-origin viruses.
The H1N8 virus was identified in avian influenza-related environments in China for the first time and may have served as a gene carrier involved in the evolution of the H7N9 virus in poultry. This work further emphasizes the importance of avian influenza virus surveillance, especially in live poultry markets (LPMs). Active surveillance of avian influenza in LPMs is a major pillar supporting avian influenza control and response.
KEYWORDS: Avian influenza virus; H1N8 subtype; Live poultry market
PMID: 31117981 DOI: 10.1186/s12879-019-4079-z
Keywords: Avian Influenza; Poultry; Live poultry markets; China; Reassortant strain; H1N1; H1N2; H7N9.