External otitis among swimmers and nonswimmers.

Studies were undertaken between the summers of 1970 and 1974 to determine the effects of swimming on the incidence of external otitis and on the isolation of Pseudomonas aeruginosa from infected outer ears. The frequency of "earaches" reported by swimmers during a telephone survey conducted during the summer of 1971 was 2.4 times the frequency reported by nonswimmers. Furthermore, the risk of a swimmer acquiring external otitis, determined from reports of outer-ear infections received from physicians during the same period, was approximately five times as great as the risk to nonswimmers. Swimming also increased the risk of P aeruginosa involvement in otitis externa, and reported infections among swimmers tended to be more severe than infections among nonswimmers.