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With no or low virulence in poultry, avian influenza A(H7N9) virus has caused severe infections in humans. In the current fifth epidemic wave, a highly pathogenic avian influenza (HPAI) H7N9 virus emerged. The insertion of four amino acids (KRTA) at the haemagglutinin (HA) cleavage site enabled trypsin-independent infectivity of this virus. Although maintaining dual receptor-binding preference, its HA antigenicity was distinct from low-pathogenic avian influenza A(H7N9). The neuraminidase substitution R292K conferred a multidrug resistance phenotype.


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  1. Gao R, Cao B, Hu Y, Feng Z, Wang D, Hu W, et al. Human infection with a novel avian-origin influenza A (H7N9) virus. N Engl J Med. 2013;368(20):1888-97. PMID: 23577628 
  2. World Health Organization (WHO). Human infection with avian influenza A(H7N9) virus – China. Disease outbreak news. Geneva: WHO; 2017. Available from:http://www.who.int/csr/don/27-february-2017-ah7n9-china/en/
  3. World Organisation for Animal Health (OIE). Manual of diagnostic tests and vaccines for terrestrial animals. Chapter 2.3.4. Avian influenza (infection with avian influenza viruses). Paris: OIE; [Accessed: 2 May 2017]. Available from: http://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/2.03.04_AI.pdf
  4. Zhou J, Wang D, Gao R, Zhao B, Song J, Qi X, et al. Biological features of novel avian influenza A (H7N9) virus. Nature. 2013;499(7459):500-3.  https://doi.org/10.1038/nature12379  PMID: 23823727 
  5. Shi Y, Zhang W, Wang F, Qi J, Wu Y, Song H, et al. Structures and receptor binding of hemagglutinins from human-infecting H7N9 influenza viruses. Science. 2013;342(6155):243-7.  https://doi.org/10.1126/science.1242917  PMID: 24009358 
  6. Childs RA, Palma AS, Wharton S, Matrosovich T, Liu Y, Chai W, et al. Receptor-binding specificity of pandemic influenza A (H1N1) 2009 virus determined by carbohydrate microarray. Nat Biotechnol. 2009;27(9):797-9.  https://doi.org/10.1038/nbt0909-797  PMID: 19741625 
  7. Chandrasekaran A, Srinivasan A, Raman R, Viswanathan K, Raguram S, Tumpey TM, et al. Glycan topology determines human adaptation of avian H5N1 virus hemagglutinin. Nat Biotechnol. 2008;26(1):107-13.  https://doi.org/10.1038/nbt1375  PMID: 18176555 
  8. Benton DJ, Wharton SA, Martin SR, McCauley JW. Role of Neuraminidase in Influenza A(H7N9) Receptor Binding. J Virol. 2017;JVI.02293-16.  https://doi.org/10.1128/JVI.02293-16  PMID: 28356530 
  9. World Health Organization (WHO) Collaborating Centers from Reference and Research on Influenza. Concepts and procedures for laboratory-based influenza surveillance / prepared by the WHO Collaborating Centers for Reference and Research on Influenza. 1982: Washington DC: United States Department of Health and Human Services. p. pB17-35.
  10. Hurt AC, Holien JK, Barr IG. In vitro generation of neuraminidase inhibitor resistance in A(H5N1) influenza viruses. Antimicrob Agents Chemother. 2009;53(10):4433-40.  https://doi.org/10.1128/AAC.00334-09  PMID: 19651908 
  11. Okomo-Adhiambo M, Nguyen HT, Abd Elal A, Sleeman K, Fry AM, Gubareva LV. Drug susceptibility surveillance of influenza viruses circulating in the United States in 2011-2012: application of the WHO antiviral working group criteria. Influenza Other Respi Viruses. 2014;8(2):258-65.  https://doi.org/10.1111/irv.12215  PMID: 24299049 
  12. Walther T, Karamanska R, Chan RW, Chan MC, Jia N, Air G, et al. Glycomic analysis of human respiratory tract tissues and correlation with influenza virus infection. PLoS Pathog. 2013;9(3):e1003223.  https://doi.org/10.1371/journal.ppat.1003223  PMID: 23516363 
  13. Webster RG, Govorkova EA. Continuing challenges in influenza. Ann N Y Acad Sci. 2014;1323(1):115-39.  https://doi.org/10.1111/nyas.12462  PMID: 24891213 

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