Tinea corporis in 4 personnel on a pediatric ward prompted an investigation through which 10 cases of nosocomial tinea corporis were eventually identified. The outbreak, caused by Trichophyton tonsurans, was traced to a corticosteroid-treated patient whose tinea infection had gone undiagnosed for 5 weeks. The attack rate for tinea corporis in personnel who had contact with the patient was 30%. Transmission appeared to have occurred primarily by direct contact with the patient because infected personnel, compared with uninfected controls, had more than twice as much direct contact (6.2 hours vs. 2.6 hours, P = 0.052). Soiled linen probably was the source of infection in two workers who had only indirect contact with the patient. This outbreak illustrates that substantial nosocomial transmission of T. tonsurans can occur and suggests that barrier precautions should be used by hospital personnel who handle infected patients or their soiled linens.
