An outbreak of influenza(type A) occurred in a ward at a university hospital in February 2013. A total of 17people (5 patients and 12 staffs) suffered and it took 8 days from the recognition to the end of the outbreak. We implementedprecautions for droplet infection including the wearing of surgical masks, restriction on working of the suffering staffs, andisolation of the suffering patients. We also restricted the admission to the ward and the acceptance of patients on EmergencyDivision for 7 days. We speculated that the reason for the early termination of the outbreak, even in the endemic season oninfluenza, was the implementation of the aggressive detection of symptomatic individuals using virus-detection kits, thethorough precautions including the restriction on working, isolation, and ward closure
