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How many countries had been affected by H1N1 by mid-January 2010?
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influenza pandemic (H1N1) of 2009
Doctors at the Mexico City Navy Hospital wearing protective gear as they tend to patients complaining of H1N1 flu-like symptoms.
By mid-January 2010, the influenza pandemic (H1N1) of 2009 had affected people in more than 209 countries worldwide.1