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Updated: Jun 25, 2026
05:59
Nasal Wipes for Influenza A Virus Detection and Isolation from Swine
Published on: December 4, 2015
Animal influenza epidemiology.
M F Ducatez1, R G Webster, R J Webby
1Department of Infectious Diseases, St. Jude Children's Research Hospital, 332 N. Lauderdale, Memphis, TN 38105, USA.
Vaccine
|February 21, 2009
Summary
Influenza A viruses in aquatic birds can evolve into subtypes that infect other species. This review examines three examples, H5N1, H9N2, and H3N2, highlighting their complex cross-species transmission and evolution.
Area of Science:
- Virology
- Epidemiology
- Infectious Diseases
Background:
- Influenza A viruses naturally circulate in aquatic birds, with numerous antigenic subtypes.
- Only a subset of these avian influenza A virus subtypes successfully transmit to other avian and mammalian hosts.
- Understanding cross-species transmission is crucial for predicting and controlling influenza outbreaks.
Purpose of the Study:
- To review the complex epidemiology of influenza A virus cross-species transmission.
- To examine three specific examples of successful interspecies transmission: avian H5N1, H9N2, and H3N2 viruses.
- To illustrate the diverse evolutionary and spread patterns of influenza A viruses between species.
Main Methods:
- Review of existing literature on influenza A virus cross-species transmission.
- Focus on three case studies: avian H5N1, H9N2, and H3N2 viruses.
- Comparative analysis of transmission routes, host adaptation, and evolutionary dynamics.
Main Results:
- Avian influenza A viruses H5N1 and H9N2 have demonstrated significant interspecies transmission.
- Influenza A virus H3N2 has transmitted from aquatic birds to humans and subsequently to swine.
- These selected examples exhibit varied patterns of spread and evolution, underscoring epidemiological complexity.
Conclusions:
- Cross-species transmission of influenza A viruses is a complex phenomenon with diverse outcomes.
- The selected examples (H5N1, H9N2, H3N2) demonstrate different pathways and evolutionary trajectories following interspecies transmission.
- Studying these specific viral transmissions provides insights into the broader epidemiology of influenza A viruses and pandemic potential.
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