OmniVira

Biological characterisation of the emerged highly pathogenic avian influenza (HPAI) A(H7N9) viruses in humans, in mainland China, 2016 to 2017.

Wenfei Zhu1,2 Jianfang Zhou1,2 Zi Li1,2 Lei Yang1 Xiyan Li1 Weijuan Huang1 Sumei Zou1 Wenbing Chen1 Hejiang Wei1 Jing Tang1 Liqi Liu1 Jie Dong1 Dayan Wang1 Yuelong Shu1
Affiliations 2 institutions
  1. National Institute for Viral Disease Control and Prevention, China Centers for Disease Control and Prevention, Key Laboratory for Medical Virology, National Health and Family Planning Commission, Beijing, China.
  2. These authors contributed equally to this work.
PMID28537546 DOI10.2807/1560-7917.ES.2017.22.19.30533 Year2017 Journal Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin Euro Surveill Languageeng Statusppublish

Abstract

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.

Supporting text Virus Host Location
Antigenic analysis 1 Drug sensitivity 1 Highly pathogenic H7N9 viruses 1 HPAI 19 Receptor binding profile 1 Disease Outbreaks 170 Animals 1948 Antiviral Agents 21 China 229 Female 289 Hemagglutinin Glycoproteins, Influenza Virus 180 Humans 1440 Influenza A Virus, H7N9 Subtype 87 Influenza in Birds 341 Influenza, Human 286 Neuraminidase 62 Poultry 112 Viral Load 36 Virulence 108

Evidence records

3 total
Functional Mechanism
3 records · 2 evidence types
Evidence type Receptor Usage
1 records
OVE2635 Receptor Usage
Key finding

The highly pathogenic avian influenza H7N9 virus maintained dual receptor-binding preference, indicating use of both avian- and human-type receptors.

Virus
Influenza A virus H7N9
Host
human Homo sapiens Experimental system birds Aves Experimental system
Location
Not specified
Supporting text

Although maintaining dual receptor-binding preference, its HA antigenicity was distinct from low-pathogenic avian influenza A(H7N9).

Method
receptor-binding assay | haemagglutinin receptor-binding analysis
Receptors
avian-type receptor | human-type receptor
Evidence type Molecular Adaptation
2 records
OVE2632 Molecular Adaptation
Key finding

Insertion of four amino acids (KRTA) at the HA cleavage site in highly pathogenic avian influenza (HPAI) H7N9 confers trypsin-independent infectivity, indicating an adaptive mechanism linked to virulence and host-entry capability.

Virus
Influenza A virus H7N9
Host
Not specified
Location
Not specified
Supporting text

The insertion of four amino acids (KRTA) at the haemagglutinin (HA) cleavage site enabled trypsin-independent infectivity of this virus.

Genes or proteins
haemagglutinin (HA)
Mutations
KRTA insertion at HA cleavage site
Mechanism types
host entry | virulence adaptation
OVE2634 Molecular Adaptation
Key finding

Neuraminidase substitution R292K in highly pathogenic avian influenza (HPAI) H7N9 confers a multidrug resistance phenotype, representing replication adaptation.

Virus
Influenza A virus H7N9
Host
Not specified
Location
Not specified
Supporting text

The neuraminidase substitution R292K conferred a multidrug resistance phenotype.

Genes or proteins
neuraminidase
Mutations
R292K
Mechanism types
replication adaptation