Internal Gene Cassette From a Human-Origin H7N9 Influenza Virus Promotes the Pathogenicity of H9N2 Avian Influenza Virus in Mice

There were five outbreaks of H7N9 influenza virus in humans in China since it emerged in 2013, infecting >1000 people. The H7N9 low pathogenic influenza virus was inserted into four amino acids in the HA protein cleavage site to mutate into the H7N9 highly pathogenic virus. This emerging virus caused 15 outbreaks in chickens from the end of 2016 to date. Two H7N9 avian influenza virus (AIV) strains, A/chicken/Guangdong/A46/2013 (LPAIV) and A/chicken/Guangdong/Q29/2017 (HPAIV), were selected to compare the pathogenicity and transmissibility between H7N9 LPAIVs and HPAIVs in chickens. We inoculated 3- to 4-week-old specific-pathogen-free (SPF) chickens with 6 log10EID50/0.1 mL viruses via the ocular-nasal route and co-housed four chickens in each group. The inoculated chicken mortality rate in the A46 and Q29 groups was 1/5 and 5/5, respectively. Q29 virus replication was more efficient compared to the A46 virus in inoculated chickens. Infected chickens initiated viral shedding to naïve contact chickens through respiratory and digestive routes. Both viruses transmitted between chickens by naïve contact, but the Q29 virus had a higher pathogenicity in contact chickens than the A46 virus. Compared with early H7N9 LPAIVs, the pathogenicity and transmissibility of the emerging H7N9 HPAIV was stronger in chickens, indicating that H7N9 influenza virus may continue to threaten human and poultry health.

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Assessment of Antiviral Properties of Peramivir against H7N9 Avian Influenza Virus in an Experimental Mouse Model

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01885-15 ◽

2015 ◽

Vol 59 (12) ◽

pp. 7255-7264 ◽

Cited By ~ 3

Author(s):

Amber Farooqui ◽

Linxi Huang ◽

Suwu Wu ◽

Yingmu Cai ◽

Min Su ◽

...

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

Mouse Model ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Antiviral Treatment ◽

Clinical Signs ◽

Influenza Virus Infection ◽

H7n9 Influenza Virus ◽

H7n9 Influenza

ABSTRACTThe H7N9 influenza virus causes a severe form of disease in humans. Neuraminidase inhibitors, including oral oseltamivir and injectable peramivir, are the first choices of antiviral treatment for such cases; however, the clinical efficacy of these drugs is questionable. Animal experimental models are essential for understanding the viral replication kinetics under the selective pressure of antiviral agents. This study demonstrates the antiviral activity of peramivir in a mouse model of H7N9 avian influenza virus infection. The data show that repeated administration of peramivir at 30 mg/kg of body weight successfully eradicated the virus from the respiratory tract and extrapulmonary tissues during the acute response, prevented clinical signs of the disease, including neuropathy, and eventually protected mice against lethal H7N9 influenza virus infection. Early treatment with peramivir was found to be associated with better disease outcomes.

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Phylogenetic Analysis of H7N9 Avian Influenza Virus Based on a Novel Mathematical Descriptor

BioMed Research International ◽

10.1155/2014/519787 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9

Author(s):

Yusheng Bai ◽

Tingting Ma ◽

Yuhua Yao ◽

Qi Dai ◽

Ping-an He

Keyword(s):

Phylogenetic Analysis ◽

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Phylogenetic Trees ◽

Graphical Representation ◽

H7n9 Influenza Virus ◽

Two Samples ◽

H7n9 Influenza ◽

3D Graphical Representation

A new mathematical descriptor was proposed based on 3D graphical representation. Using the method, we construct the phylogenetic trees of nine proteins of H7N9 influenza virus to analyze the originated source of H7N9. The results show that the evolution route of H7N9 avian influenza is from America through Europe to Asia. Furthermore, two samples collected from environment in Nanjing and Zhejiang and one sample collected from chicken are the sources of H7N9 influenza virus that infected human in China.

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