Epidemic curves of two selected influenza A(H1N1) outbreaks at school.

<p>A, epidemic curve of influenza A(H1N1) new cases in a middle school, 2013 (The starting date of the outbreak was on January 8, and the duration of the outbreak was 19 days). B, epidemic curve of influenza A(H1N1) new cases in a college, 2009 (The starting date of the outbreak was on November 7, and the duration of the outbreak was 23 days).