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ABSTRACT Influenza viruses cause annual epidemics and occasional pandemics that have claimed the lives of millions. The emergence of new strains will continue to pose challenges to public

health and the scientific communities. A prime example is the recent emergence of swine-origin H1N1 viruses that have transmitted to and spread among humans, resulting in outbreaks

internationally. Efforts to control these outbreaks and real-time monitoring of the evolution of this virus should provide us with invaluable information to direct infectious disease control

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EVOLUTION OF H1 SWINE INFLUENZA A VIRUSES ISOLATED IN BELGIUM AND THE NETHERLANDS FROM 2014 THROUGH 2019 Article Open access 28 May 2021 NOVEL REASSORTANT SWINE H3N2 INFLUENZA A VIRUSES IN

GERMANY Article Open access 31 August 2020 POTENTIAL PANDEMIC RISK OF CIRCULATING SWINE H1N2 INFLUENZA VIRUSES Article Open access 13 June 2024 REFERENCES * Kobasa, D. et al. Aberrant innate

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_Lancet_ 367, 475–481 (2006) CAS  PubMed  PubMed Central  Google Scholar  Download references ACKNOWLEDGEMENTS We apologize to our colleagues whose critical contributions to influenza virus

research could not be cited owing to the number of references permitted. We thank K. Wells for editing the manuscript. We also thank M. Ozawa and others in our laboratories who contributed

to the data cited in this review. Our original research was supported by National Institute of Allergy and Infectious Diseases Public Health Service research grants; by the Center for

Research on Influenza Pathogenesis (CRIP) funded by the National Institute of Allergy and Infectious Diseases (Contract HHSN266200700010C), Grant-in-Aid for Specially Promoted Research, by a

contract research fund for the Program of Founding Research Centers for Emerging and Reemerging Infectious Diseases from the Ministry of Education, Culture, Sports, Science, and Technology,

by grants-in-aid from the Ministry of Health and by ERATO (Japan Science and Technology Agency). G.N. is named as co-inventor on several patents about influenza virus reverse genetics

and/or the development of influenza virus vaccines or antivirals. Y.K. is named as inventor/co-inventor on several patents about influenza virus reverse genetics and/or the development of

influenza virus vaccines or antivirals. Figures 1 and 2 were modified from Orthomyxoviruses: influenza, in Topley and Wilson's Microbiology and Microbial Infections: Virology (Hodder

Arnold, 2005); Fig. 3 was modified from Orthomyxoviruses, in Fields Virology (Lippincott Williams & Wilkins, 2007). AUTHOR CONTRIBUTIONS G.N. wrote the manuscript. T.N. provided the

electron microscopic picture. Y.K. also wrote the manuscript. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison,

Wisconsin 53711, USA, Gabriele Neumann & Yoshihiro Kawaoka * International Research Center for Infectious Diseases,, Takeshi Noda & Yoshihiro Kawaoka * Division of Virology,

Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo 108-8639, Japan Yoshihiro Kawaoka * ERATO Infection-Induced Host Responses Project, Japan

Science and Technology Agency, Saitama 332-0012, Japan Yoshihiro Kawaoka Authors * Gabriele Neumann View author publications You can also search for this author inPubMed Google Scholar *

Takeshi Noda View author publications You can also search for this author inPubMed Google Scholar * Yoshihiro Kawaoka View author publications You can also search for this author inPubMed 

Google Scholar CORRESPONDING AUTHOR Correspondence to Yoshihiro Kawaoka. ETHICS DECLARATIONS COMPETING INTERESTS [Competing Interests: Y.K. has received speaker’s honoraria from Chugai

Pharmaceuticals, Novartis, Sankyo, Toyama Chemical, Wyeth and GlaxoSmithKline; grant support from Chugai Pharmaceuticals, Daiichi Sankyo Pharmaceutical and Toyama Chemical; consulting fee

from Theraclone Sciences and Fort Dodge Animal Health; and is a founder of FluGen. G.N. has received consulting fee from Theraclone Sciences and is a founder of FluGen.] ADDITIONAL

INFORMATION The authors declare competing financial interests: details accompany the full-text HTML version of the paper at www.nature.com/nature. POWERPOINT SLIDES POWERPOINT SLIDE FOR FIG.

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THIS ARTICLE Neumann, G., Noda, T. & Kawaoka, Y. Emergence and pandemic potential of swine-origin H1N1 influenza virus. _Nature_ 459, 931–939 (2009). https://doi.org/10.1038/nature08157

Download citation * Received: 12 May 2009 * Accepted: 26 May 2009 * Published: 14 June 2009 * Issue Date: 18 June 2009 * DOI: https://doi.org/10.1038/nature08157 SHARE THIS ARTICLE Anyone

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