Indian Journal of Virology

, Volume 23, Issue 1, pp 12–17

Pandemic Influenza A H1N1 (2009) Virus: Lessons from the Past and Implications for the Future

  • Madhu Khanna
  • Binod Kumar
  • Ankit Gupta
  • Prashant Kumar
Review Article


The recent pandemic by novel influenza A (H1N1) 2009 (pH1N1) virus is an emerging viral infection, being of significant international concern and requires intensive research. The virus spread in pandemic proportions, and continues to be in the post-pandemic phase. Since, the pH1N1 is still circulating in the community, monitoring is required during the post-pandemic period. The pH1N1 defied influenza seasonality and rapidly became dominant over the seasonal influenza viruses. This new strain was antigenically different from the seasonal H1N1 influenza strains due to the genetic re-assortment. Surprisingly, this new reassortant virus emerged at the end of influenza season, caused a sudden toll of mild illness and is now co-circulating with the seasonal strains. The recent outbreak of pH1N1 consolidates the fact that a new reassortant virus may have originated in animal reservoirs and got transferred to human who were in close contact with these animals. There is a continued need for multisite surveillance to detect potentially dangerous influenza strains, which may emerge and establish themselves in human population. This review is an attempt to address the lessons learnt from the recent influenza pandemic and the future implications for prevention and control of influenza.


Influenza A H1N1 virus Pandemic Re-assortment Antiviral therapy 


  1. 1.
    Barry JM. The great influenza. The story of the deadliest pandemic in history. London: Penguin Books; 2005.Google Scholar
  2. 2.
    Basler CF, Aguilar PV. Progress in identifying virulence determinants of the 1918 H1N1 and the Southeast Asian H5N1 influenza A viruses. Antiviral Res. 2008;79:166–78.PubMedCrossRefGoogle Scholar
  3. 3.
    Baz M, Abed Y, Papenburg J, Bouhy X, Hamelin M, Boivin M. Emergence of oseltamivir-resistant pandemic H1N1 virus during prophylaxis. N Eng J Med. 2009;361:2296–7.CrossRefGoogle Scholar
  4. 4.
    Evaluation of rapid influenza diagnostic tests for detection of novel influenza A (H1N1) virus—United States, 2009. MMWR Morb Mortal Wkly Rep. 2009;58:826–9.Google Scholar
  5. 5.
    Chen GW, Shih SR. Genomic signatures of influenza A pandemic (H1N1) 2009 virus. Emerg Infect Dis. 2009;15:1897–903.PubMedGoogle Scholar
  6. 6.
    Chia-Lin L, Chiang LC, Cheng LH, Liaw CC, El-Raze MAH, Chang FR, et al. Influenza A (H1N1) antiviral and cytotoxic agents from Ferula assa-foetida. J Nat Prod. 2009;72:1568–72.CrossRefGoogle Scholar
  7. 7.
    Eichner M, Schwehm M, Duerr HP, Witschi M, Koch D, Brockmann SO, Vidondo B. Antiviral prophylaxis during pandemic influenza may increase drug resistance. BMC Infect Dis. 2009;9:4.PubMedCrossRefGoogle Scholar
  8. 8.
    Garten RJ, Davis CT, Russel CA, Shu B, Lindstrom S, et al. Antigenic and genetic characteristics of swine-origin 2009 A (H1N1) influenza viruses circulating in humans. Science. 2009;325:197–201.PubMedCrossRefGoogle Scholar
  9. 9.
    Gibbs AJ, Armstrong JS, Downie JC. From where did the 2009 ‘swine-origin’ influenza A virus (H1N1) emerge? Virol J. 2009;6:207.PubMedCrossRefGoogle Scholar
  10. 10.
    Glass RJ, Glass LM, Beyeler WE, Min HJ. Targeted social distancing design for pandemic influenza. Emer Infect Dis. 2006;12:1671–81.CrossRefGoogle Scholar
  11. 11.
    Glezen WP. Containing the novel influenza A (H1N1) virus. Clin Infect Dis. 2010;50:869–70.PubMedCrossRefGoogle Scholar
  12. 12.
    Goldkind SF, Sahin L, Gallauresi B. Enrolling pregnant women in research—lessons from the H1N1 influenza pandemic. N Engl J Med. 2010;362:2221–3.CrossRefGoogle Scholar
  13. 13.
    Guan Y, Shortridge KF, Krauss S, Webster RG. Molecular characterization of H9N2 influenza viruses: were they the donors of the ‘‘internal’’ genes of H5N1 viruses in Hong Kong? Proc Natl Acad Sci USA. 1999;96:9363–7.PubMedCrossRefGoogle Scholar
  14. 14.
    Hai R, Schmolke M, Varga ZT, Manicassamy B, Wang TT, et al. PB1-F2 expression by the 2009 pandemic H1N1 influenza virus has minimal impact on virulence in animal models. J Virol. 2010;84:4442–50.PubMedCrossRefGoogle Scholar
  15. 15.
    Hill A, Guralnick R, Wilson M, Habib F, Janies D. Evolution of drug resistance in multiple distinct lineages of H5N1 avian influenza. Infect Genet Evol. 2009;9:169–78.PubMedCrossRefGoogle Scholar
  16. 16.
    Kashyap AK, Steel J, Rubrum A, Estelles A, Briante R, et al. Protection from the 2009 H1N1 pandemic influenza by an antibody from combinatorial survivor-based libraries. PLoS Pathog. 2010;6:1000990.CrossRefGoogle Scholar
  17. 17.
    Khanna M, Kumar P, Choudhary K, Kumar B, Vijayan VK. Emerging influenza virus: a global threat. J Biosci. 2008;33:475–82.PubMedCrossRefGoogle Scholar
  18. 18.
    Khanna M, Kumar B, Gupta N, Kumar P, Vijayan VK, Kaur H. Pandemic swine influenza virus (H1N1): a threatening evolution. Indian J Microbiol. 2009;49:365–9.CrossRefGoogle Scholar
  19. 19.
    Lindstrom SE, Cox NJ, Klimov A. Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957–1972: evidence for genetic divergence and multiple reassortment events. Virology. 2004;328:101–19.PubMedCrossRefGoogle Scholar
  20. 20.
    Lowen AC, Mubareka S, Steel J, Palese P. Influenza virus transmission is dependent on relative humidity and temperature. PLoS Pathog. 2007;193(10):1470–4.Google Scholar
  21. 21.
    Memoli MJ, Hrabal RJ, Hassantoufighi A, Eichelberger MC, Taubenberger JK. Rapid selection of oseltamivir- and peramivir-resistant pandemic H1N1 virus during therapy in 2 immunocompromised hosts. Clin Infect Dis. 2010;50:1252–5.PubMedCrossRefGoogle Scholar
  22. 22.
    Merler S, Ajelli M, Rizzo C. Age-prioritized use of antivirals during an influenza pandemics. BMC Infect Dis. 2009;9:117.PubMedCrossRefGoogle Scholar
  23. 23.
    Mishra AC, Chadha MS, Choudhary ML, Potdar VA. Pandemic Influenza (H1N1) 2009 Is Associated with Severe Disease in India. PLoS One. 2010;5:e10540.PubMedCrossRefGoogle Scholar
  24. 24.
    Moscona A. Global transmission of oseltamivir-resistant influenza. N Engl J Med. 2009;360:953–6.PubMedCrossRefGoogle Scholar
  25. 25.
    Ariano RE, Sitar DS, Zelenitsky SA, Zarychanski R, Pisipati A, Ahern S, Kanji S, Rello L, Kumar A. Enteric absorption and pharmacokinetics of oseltamivir in critically ill patients with pandemic (H1N1) influenza. CMAJ. 2010;182:357–63.Google Scholar
  26. 26.
    Operario DJ, Moser MJ, St.George K. Highly sensitive and quantitative detection of the H274Y oseltamivir resistance mutation in seasonal A/H1N1 influenza. J Clin Microbiol. 2010;48:3517–24.PubMedCrossRefGoogle Scholar
  27. 27.
    Poalillo FE, Geiling J, Jimenez EJ. Healthcare personnel and nosocomial transmission of pandemic 2009 influenza. Crit Care Med. 2010;38:98–102.CrossRefGoogle Scholar
  28. 28.
    Rambaut A, Holmes E. The early molecular epidemiology of the swine-origin A/H1N1 human influenza pandemic. PLoS Curr. 2009;1:RRN1003.PubMedCrossRefGoogle Scholar
  29. 29.
    Shih SR, Chu TY, Reddy GR, Tseng SN, Chen HL, Tang WF, et al. Pyrazole compound BPR1P0034 with potent and selective anti-influenza virus activity. J Biomed Sci. 2010;17:13.PubMedCrossRefGoogle Scholar
  30. 30.
    Siston AM, Rasmussen SA, Honein MA, Fry AM, Seib K, Callaghan WM, et al. Pandemic 2009 influenza A (H1N1) virus illness among pregnant women in the United States. JAMA. 2010;303:1517–25.PubMedCrossRefGoogle Scholar
  31. 31.
    Tandale BV, Pawar SD, Gurav YK, Chadha MS, Koratkar SS, et al. Seroepidemiology of pandemic influenza A (H1N1) 2009 virus infections in Pune, India. BMC Infect Dis. 2010;10:255.PubMedCrossRefGoogle Scholar
  32. 32.
    Torres JP, O’Ryan M, Herve B, Espinoza R, Acuna G, Manalich J, et al. Impact of the novel influenza A (H1N1) during the 2009 autumn‐winter season in a large hospital setting in Santiago, Chile. Clin Infect Dis. 2010;50:860–8.PubMedCrossRefGoogle Scholar
  33. 33.
    Triana-Baltzer GB, Gubareva LV, Nicholls JM, Pearce MB, Mishin VP. Novel pandemic influenza A (H1N1) viruses are potently inhibited by DAS181, a sialidase fusion protein. PLoS One. 2009;4(11):7788.CrossRefGoogle Scholar
  34. 34.
    Wilson K, Brownstein JS, Fidler DP. Strengthening the international health regulations: lessons from the H1N1 pandemic. Health Policy Plan. 2010;25:505–9.PubMedCrossRefGoogle Scholar
  35. 35.
    Wu JT, Leung GM, Lipsitch M, Cooper BS, Riley S. Hedging against antiviral resistance during the next influenza pandemic using small stockpiles of an alternative chemotherapy. PLoS Med. 2009;6:1000085.CrossRefGoogle Scholar

Copyright information

© Indian Virological Society 2012

Authors and Affiliations

  • Madhu Khanna
    • 1
  • Binod Kumar
    • 1
  • Ankit Gupta
    • 1
  • Prashant Kumar
    • 1
  1. 1.Department of Respiratory Virology, Vallabhbhai Patel Chest InstituteUniversity of DelhiDelhiIndia

Personalised recommendations