摘要
Pathogenic H7N9 influenza viruses continue to pose a public health concern. The H7N9 virus has caused five outbreak waves of human infections in China since 2013. In the present study, a novel H7N9 strain(A/Guangdong/8 H324/2017) was isolated from a female patient with severe respiratory illness during the fifth wave of the 2017 H7N9 epidemic. Phylogenetic analysis showed that the H7N9 viruses collected during the fifth wave belong to two different lineages: the Pearl River Delta lineage and the Yangtze River Delta lineage. The novel isolate is closely related to the Pearl River Delta H7N9 viruses, which were isolated from patients in Guangdong Province. The novel H7N9 isolate has an insertion of three basic amino acids in the cleavage site of hemagglutinin(HA), which may enhance virulence in poultry. The 2017 isolate also possesses an R292 K substitution in the neuraminidase(NA)protein, which confers oseltamivir resistance. This study highlights the pandemic potential of the novel H7N9 virus in mammals;thus, future characterization and surveillance is warranted.
Pathogenic H7N9 influenza viruses continue to pose a public health concern. The H7N9 virus has caused five outbreak waves of human infections in China since 2013. In the present study, a novel H7N9 strain（A/Guangdong/8 H324/2017） was isolated from a female patient with severe respiratory illness during the fifth wave of the 2017 H7N9 epidemic. Phylogenetic analysis showed that the H7N9 viruses collected during the fifth wave belong to two different lineages： the Pearl River Delta lineage and the Yangtze River Delta lineage. The novel isolate is closely related to the Pearl River Delta H7N9 viruses, which were isolated from patients in Guangdong Province. The novel H7N9 isolate has an insertion of three basic amino acids in the cleavage site of hemagglutinin（HA）, which may enhance virulence in poultry. The 2017 isolate also possesses an R292 K substitution in the neuraminidase（NA）protein, which confers oseltamivir resistance. This study highlights the pandemic potential of the novel H7N9 virus in mammals;thus, future characterization and surveillance is warranted.
基金
supported by the National Major Special Program of Science and Technology of China(2017ZX10305501-010,AWS15J006)
the Guangzhou Science and Technology Program(201508020106,2014Y-00550,2014Y2-00031)
partly by the Key Project of the State Key Laboratory of Pathogen and Biosecurity(SKLPBS1407)
