Risk assessment of the newly emerged H7N9 avian influenza viruses
Emerging Microbes & Infections·
- DOI
- 10.1080/22221751.2023.2172965
- PMID
- 36714929
- PMCID
- PMC9930780
- OpenAlex
- W4318472520
- Study type
- Journal article
- Publisher
- Informa UK Limited
- Article type
- journal-article
- Integrity
- current
Why this research matters now
Findings point to reduced human-receptor binding in recent H7N9 strains while highlighting antigenic drift that may necessitate updating candidate vaccine viruses, with implications for poultry vaccination strategy in China.
Structured evidence summary
Research question
The study examines the zoonotic risk posed by recently emerged H7N9 avian influenza viruses by characterizing receptor binding, stability, replication, and antigenic properties of reassortant viruses carrying recent H7N9 surface glycoproteins.
Study design
Laboratory characterization of rescued reassortant viruses (HA and NA from recent H7N9 isolates on a PR8 internal-gene backbone), assessing receptor binding, fusion pH, thermal stability, plaque morphology, in ovo replication, and cross-reactivity with human monoclonal antibodies and ferret antisera.
Population and setting
In vitro and in ovo systems (MDCK cells and embryonated eggs) using H7N9 isolates from recent epidemic waves in China, compared with earlier-wave H7N9 reference strains; no human or animal cohort is described.
Main findings
Recent H7N9 isolates lost or retained only weak human-type sialic acid receptor binding, formed larger MDCK plaques, replicated to higher titres in ovo, showed greater acid stability but reduced thermal stability, and exhibited poor cross-reactivity with existing human mAbs and ferret antisera. The authors conclude the recent viruses display typical avian features and suggest reduced zoonotic risk but continued poultry threat.
Public-health relevance
Findings point to reduced human-receptor binding in recent H7N9 strains while highlighting antigenic drift that may necessitate updating candidate vaccine viruses, with implications for poultry vaccination strategy in China.
Important limitations
The summary is limited to the supplied single-article abstract and metadata; the original paper is required for decision-grade interpretation. The supplied abstract does not enumerate explicit limitations.
GIDS interpretation
The article addresses an avian-influenza topic covered by GIDS classification (H7N9, Influenza, China, One Health, Vaccination) and is discoverable through these links, but the supplied evidence does not establish any connection to a live surveillance signal.
Related GIDS surveillance
Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.
Evidence relationships
This article has 11 auditable classifier relationships to diseases, places, topics, and study design.