The evolution and genetic diversity of avian influenza A(H9N2) viruses in Cambodia, 2015 – 2016

Autoři: Annika Suttie aff001;  Songha Tok aff001;  Sokhoun Yann aff001;  Ponnarath Keo aff001;  Srey Viseth Horm aff001;  Merryn Roe aff003;  Matthew Kaye aff003;  San Sorn aff004;  Davun Holl aff004;  Sothyra Tum aff004;  Ian G. Barr aff002;  Aeron C. Hurt aff003;  Andrew R. Greenhill aff002;  Erik A. Karlsson aff001;  Dhanasekaran Vijaykrishna aff003;  Yi-Mo Deng aff003;  Philippe Dussart aff001;  Paul F. Horwood aff001
Působiště autorů: Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, Phnom Penh, Cambodia aff001;  School of Health and Life Sciences, Federation University, Churchill, Australia aff002;  WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia aff003;  National Animal Health and Production Research Institute, General Directorate of Animal Health and Production, Cambodian Ministry of Agriculture, Forestry and Fisheries, Phnom Penh, Cambodia aff004;  Department of Microbiology and Immunology, The University of Melbourne, Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia aff005;  Department of Microbiology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria Australia aff006;  College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Australia aff007
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article


Low pathogenic A(H9N2) subtype avian influenza viruses (AIVs) were originally detected in Cambodian poultry in 2013, and now circulate endemically. We sequenced and characterised 64 A(H9N2) AIVs detected in Cambodian poultry (chickens and ducks) from January 2015 to May 2016. All A(H9) viruses collected in 2015 and 2016 belonged to a new BJ/94-like h9-4.2.5 sub-lineage that emerged in the region during or after 2013, and was distinct to previously detected Cambodian viruses. Overall, there was a reduction of genetic diversity of H9N2 since 2013, however two genotypes were detected in circulation, P and V, with extensive reassortment between the viruses. Phylogenetic analysis showed a close relationship between A(H9N2) AIVs detected in Cambodian and Vietnamese poultry, highlighting cross-border trade/movement of live, domestic poultry between the countries. Wild birds may also play a role in A(H9N2) transmission in the region. Some genes of the Cambodian isolates frequently clustered with zoonotic A(H7N9), A(H9N2) and A(H10N8) viruses, suggesting a common ecology. Molecular analysis showed 100% of viruses contained the hemagglutinin (HA) Q226L substitution, which favours mammalian receptor type binding. All viruses were susceptible to the neuraminidase inhibitor antivirals; however, 41% contained the matrix (M2) S31N substitution associated with resistance to adamantanes. Overall, Cambodian A(H9N2) viruses possessed factors known to increase zoonotic potential, and therefore their evolution should be continually monitored.

Klíčová slova:

Antimicrobial resistance – Bird genomics – Phylogenetic analysis – Phylogenetics – Poultry – Viral genomics – Zoonoses


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