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    James M. Steckelberg, M.D.

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Question

H1N1 flu (swine flu) pandemic: What does it mean?

Why is swine flu a pandemic? Has H1N1 flu turned out to be much worse than expected?

Answer

from James M. Steckelberg, M.D.

It's not actually worse, just — as predicted — widespread. That's why the World Health Organization (WHO) issued a level 6 influenza pandemic alert — the highest level alert of its kind.

A World Health Organization phase 6 pandemic indicates that influenza due to the novel H1N1 swine flu is occurring in multiple countries around the world and that human infection is widespread. The classification does not reflect the severity of individual infections.

The alert level is also notable because:

  • The swine flu H1N1 virus is globally widespread at the community level.
  • The chain of person-to-person transmission is no longer clear in some areas, so testing all suspected cases is not feasible.
  • The groups most severely affected differ from those who typically develop seasonal flu complications.
  • Rates of severe illness and death from novel H1N1 influenza may be unusually high in the developing world.

The WHO continues to recommend against travel restrictions, quarantines and border closings.

Next question
H1N1 flu (swine flu) symptoms: Is fever always present?
References
  1. World now at the start of 2009 influenza pandemic. Statement to the press by WHO Director-General Margaret Chan. http://www.who.int/mediacentre/news/statements/2009/h1n1_pandemic_phase6_20090611/en/index.html. Accessed June 11, 2009.
  2. Steckelberg JM (expert opinion). Mayo Clinic, Rochester, Minn. June 11, 2009.

AN02013

Aug. 5, 2009

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