Abstract
The first reported human case of H7N9 influenza virus infection in Shanghai prompted a survey of local avian strains of influenza virus, involving the analysis of a large number of samples taken from poultry, wild birds, horses, pigs, dogs and mice. Seven instances of H7N9 virus infection were identified by real-time RT-PCR (1.47 % of samples), all in chickens sold in live-poultry markets. H7N9 antibody was not detected in serum samples collected from local poultry farms since 2006. The two H7N9 virus strains in the live-poultry markets and one H9N2 virus strain in the same market were genetically characterized. Resequencing of two of the seven isolates confirmed that they closely resembled H7N9 virus strains characterized elsewhere. Various strains co-exist in the same market, presenting a continuing risk of strain re-assortment. The closure of live-poultry markets has been an effective short-term means of minimizing human exposure to H7N9 virus.











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This research was financially supported by a grant from Shanghai Municipal Health & Family Planning Commission (2013 QLG001).
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Ge, FF., Ju, HB., Yang, DQ. et al. Epidemiological situation and genetic analysis of H7N9 influenza viruses in Shanghai in 2013. Arch Virol 159, 3029–3041 (2014). https://doi.org/10.1007/s00705-014-2177-1
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DOI: https://doi.org/10.1007/s00705-014-2177-1


