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What is Swine Flu, or H1N1?

ByGreg Poland, M.D., Professor of Medicine, Director, Mayo Vaccine Research Group, Mayo Clinic

September 25, 2008, 1:56 PM

May 27, 2009 -- Question: What is swine flu, or H1N1?

Answer: In some respects it's just like any other influenza virus. It's a virus that causes a predominantly respiratory illness. What's unique about this swine flu is that it is a mutated type of virus so that nobody in the U.S. or probably world wide has any immunity to it. Hence it's ability to cause widespread infections.

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What is Swine Flu, or H1N1?

Up Next in News—

Judge in Lindsay Clancy case indefinitely impounds jury questionnaires

Simone Biles says 3 masked men stole luxury sports car from Chicago-area home

Capt. Chesley 'Sully' Sullenberger shares new details of Alzheimer's diagnosis, his 'last flight'

Lindsay Clancy holdout juror's attorney says defense's motion for judge to question him 'dangerous'

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