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Influenza A Virus Studies in a Mouse Model of Infection
Published on: September 7, 2017
First Human Infection with Influenza A(H1N2)v Virus - Yunnan Province, China, 2026
Lihua Chen1,2, Yaoyao Chen3, Xiaoyu Han3
1Epidemic Surveillance and Public Health Emergency Response Center, Yunnan Center for Disease Control and Prevention, Kunming City, Yunnan Province, China.
China CDC Weekly
|August 6, 2026
Summary
The first human infection with swine-origin influenza A(H1N2)v virus in China was confirmed. Investigations found no evidence of human-to-human transmission, emphasizing enhanced surveillance at the human-animal interface.
Area of Science:
- Virology
- Epidemiology
- Public Health
Background:
- Sporadic human infections with swine-origin influenza A(H1N2)v viruses are known globally, typically linked to pig exposure.
- Sustained human-to-human transmission of these variant viruses has not been previously documented.
Purpose of the Study:
- To report the first confirmed case of influenza A(H1N2)v virus infection in a human in China.
- To investigate the origin and potential for transmission of this variant influenza virus.
Main Methods:
- Laboratory confirmation of influenza A(H1N2)v infection.
- Whole-genome sequencing of the detected virus.
- Epidemiological investigation of close contacts to assess secondary transmission.
Main Results:
- The first laboratory-confirmed human case of influenza A(H1N2)v in China was identified.
- Whole-genome sequencing revealed the virus was closely related to swine influenza viruses circulating in China.
- No secondary human cases were found among close contacts, indicating no sustained human-to-human transmission.
Conclusions:
- This case underscores the need for robust surveillance of influenza-like illnesses and whole-genome sequencing for unusual influenza A infections.
- Strengthening human-animal interface surveillance and inter-sectoral collaboration within the One Health framework is crucial for early detection and risk assessment of variant influenza viruses.
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