[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]
Arch Virol. 2018 Dec 11. doi: 10.1007/s00705-018-4102-5. [Epub ahead of print]
Pathogenicity of two novel human-origin H7N9 highly pathogenic avian influenza viruses in chickens and ducks.
Tanikawa T1, Uchida Y1, Takemae N1, Tsunekuni R1, Mine J1, Liu MT2, Yang JR2, Shirakura M3, Watanabe S3, Odagiri T3, Saito T4,5.
Author information: 1 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan. 2 Center for Research, Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan. 3 Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo, 208-0011, Japan. 4 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan. firstname.lastname@example.org. 5 United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan. email@example.com.
Human infection by low-pathogenic avian influenza viruses of the H7N9 subtype was first reported in March 2013 in China. Subsequently, these viruses caused five outbreaks through September 2017. In the fifth outbreak, H7N9 virus possessing a multiple basic amino acid insertion in the cleavage site of hemagglutinin emerged and caused 4% of all human infections in that period. To date, H7N9 highly pathogenic avian influenza viruses (HPAIVs) have been isolated from poultry, mostly chickens, as well as the environment. To evaluate the relative infectivity of these viruses in poultry, chickens and ducks were subjected to experimental infection with two H7N9 HPAIVs isolated from humans, namely A/Guangdong/17SF003/2016 and A/Taiwan/1/2017. When chickens were inoculated with the HPAIVs at a dose of 10650% egg infectious dose (EID50), all chickens died within 2-5 days after inoculation, and the viruses replicated in most of the internal organs examined. The 50% lethal doses of A/Guangdong/17SF003/2016 and A/Taiwan/1/2017 in chickens were calculated as 103.3 and 104.7 EID50, respectively. Conversely, none of the ducks inoculated with either virus displayed any clinical signs, and less-efficient virus replication and less shedding were observed in ducks compared to chickens. These findings indicate that chickens, but not ducks, are highly permissive hosts for emerging H7N9 HPAIVs.
PMID: 30539262 DOI: 10.1007/s00705-018-4102-5
Keywords: Avian Influenza; H7N9; Poultry; Human; China.