Johns et al. BMC Public Health 2011, 11(Suppl 2):S3 http://www.biomedcentral.com/1471-2458/11/S2/S3 Page 6 of 9 40 35 30 25 s e s a 20 C . o N 15 10 5 0 4th of July Event Transmission building Figure 3 U.S. Air Force Academy swearing-in ceremony (Photo Courtesy of Official U.S. Air Force Academy website). Outbreak recognized Suspect Confirmed 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 /2 /2 /2 /2 /2 /3 /7 /7 /7 /7 /7 /7 /7 /7 /7 /1 /1 /1 /1 /1 /1 /1 /1 /1 /1 /2 /2 /2 /2 /2 6 6 6 6 6 6 Date of symptom onset 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 Figure 4 Confirmed, suspect cases of A/H1N1 virus infection at U.S. Air Force Academy, 2009 [17].