Limited human-to-human transmission of avian influenza A(H7N9) virus, Shanghai, China, March to April 2013
Eurosurveillance·
- DOI
- 10.2807/1560-7917.es2014.19.25.20838
- PMID
- 24993556
- PMCID
- —
- OpenAlex
- W2330840369
- Study type
- Genomic study
- Publisher
- European Centre for Disease Control and Prevention (ECDC)
- Article type
- journal-article
- Integrity
- current
Why this research matters now
The findings suggest that limited human-to-human transmission of A(H7N9) most likely occurred within this family cluster, but the absence of positive tests in other close contacts indicates limited potential for extensive human-to-human spread.
Structured evidence summary
Research question
The study investigated whether human-to-human transmission occurred in a family cluster of avian influenza A(H7N9) cases identified in Shanghai during March to April 2013.
Study design
This was an outbreak investigation combining molecular detection via real-time RT-PCR on respiratory specimens, serological testing of paired serum samples, and phylogenetic analysis of viral sequences from patients and environmental samples from wet markets.
Population and setting
The investigation focused on two family members confirmed with A(H7N9) infection and their 27 close contacts in Shanghai, China. Environmental sampling was conducted at wet markets in Minhang and Changning districts.
Main findings
Both family members developed pneumonia with highly similar clinical features and A(H7N9) infection confirmed by genetic analysis. Phylogenetic analysis showed high similarity between patient sequences and environmental samples from local wet markets. Among 27 close contacts, one had mild respiratory symptoms and another tested positive for A(H7N9) antibodies, though both were negative by RT-PCR; the remaining 25 contacts tested negative.
Public-health relevance
The findings suggest that limited human-to-human transmission of A(H7N9) most likely occurred within this family cluster, but the absence of positive tests in other close contacts indicates limited potential for extensive human-to-human spread.
Important limitations
This summary relies on the supplied single-article abstract and metadata. The original paper is required for decision-grade interpretation of surveillance or clinical implications.
GIDS interpretation
This peer-reviewed genomic study from 2014 documents an early A(H7N9) family cluster investigation and would be discoverable through queries combining avian influenza, H7N9, China, transmission dynamics, and outbreak investigation terms.
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 12 auditable classifier relationships to diseases, places, topics, and study design.