In total, 395 participants completed 1-13 weekly questionnaires each. Eighty-nine clinical and 51 nonclinical participants reported 139 and 91 respiratory illnesses, respectively. No participant reported having laboratoryconfi rmed pandemic (H1N1) 2009 infl uenza. Six reported community contact with someone who had laboratoryconfi rmed infection. One reported taking oseltamivir after contact with an infected person in the workplace. This person had 2 serum samples taken 88 days apart; both had an antibody titer of <10.