The Emergence of 2009 H1N1 Pandemic Influenza

  • Benjamin Greenbaum
  • Vladimir Trifonov
  • Hossein Khiabanian
  • Arnold Levine
  • Raul Rabadan
Part of the Birkhäuser Advances in Infectious Diseases book series (BAID)


The emergence of a novel H1N1 virus in Mexico and the USA in spring 2009 and its rapid spread around the globe has led the World Health Organization to declare the first pandemic of the twenty-first century. Employing almost real-time sequencing technologies and disseminating this information freely and widely has permitted the most intensive investigation of the origins and evolution of an influenza pandemic in the history of this disease. The small levels of sequence diversity of the first isolates permitted a realistic estimate of when the 2009 H1N1 virus first entered the human population. The rate of change in influenza RNA sequences permitted several groups to trace the origins of this virus to swine and a reassortment of North American and Eurasian swine influenza. These virus strains in turn have been traced back to swine, avian, and human virus reassortments occurring years ago in swine, all the way back to the 1918–1930 H1N1 viruses. The influenza virus sequence information spans the dimensions of time (90 years), space (locations all over the world), and hosts (birds, humans, swine, etc.). The high evolutionary rate of this virus and the growing amount of information is allowing researchers to follow its changes in the search for possible factors that could contribute to an increase in its virulence.


Influenza Virus H1N1 Virus Swine Influenza Swine Influenza Virus H1N1 Strain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



B. Greenbaum would like to acknowledge the support of Eric and Wendy Schmidt. R. Rabadan and H. Khiabanian would like to acknowledge support from Eureka (Exceptional, Unconventional Research Enabling Knowledge Acceleration) grant number 1R01LM010140-01.


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Copyright information

© Birkhäuser Basel 2011

Authors and Affiliations

  • Benjamin Greenbaum
    • 1
  • Vladimir Trifonov
    • 2
  • Hossein Khiabanian
    • 2
  • Arnold Levine
    • 1
  • Raul Rabadan
    • 2
  1. 1.The Simons Center for Systems BiologyInstitute for Advanced StudyPrincetonUSA
  2. 2.Department of Biomedical Informatics, Center for Computational Biology and BioinformaticsColumbia University College of Physicians and SurgeonsNew YorkUSA

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