Bacterial flora of airline headset devices

External otitis caused by Staphylococcus aureus was observed in two patients after they wore airline headset devices. The bacterial flora of 40 headset devices was evaluated. Bacteria were recovered from all headsets, and the number of organisms ranged from 10 to 1,200 (mean 138 +/- 246 organisms per headset). The predominant organisms recovered were S. aureus (in 12 headsets), Bacillus sp. and S. epidermidis (ten headsets each), alpha-hemolytic streptococci (in eight) and Corynebacterium sp. (in six). The effect of wearing a sterile headset for an hour was investigated using 20 volunteers. After wearing the headsets, an increase of at least two log10 colony-forming units was observed in 11 (55 per cent) of the volunteers, a decrease was observed in one (5 per cent), and no significant change in the bacterial flora was noticed in eight (40 per cent). The study demonstrates the presence of potential pathogens in headset devices and the increase in the number of endogenous flora in individuals who wear these devices.