Epidemiology of Trichophyton verrucosum infection in Rennes University Hospital, France: A 12-year retrospective study

Trichophyton verrucosum is a zoophilic dermatophyte, known as a causative agent of inflammatory mycoses of the skin and the scalp in humans. In this study, we reviewed all cases of T. verrucosum infection diagnosed in our laboratory over a 12-year period, to determine epidemiological and clinical characteristics. Among 18,340 samples analyzed, 5,186 cultured positive with dermatophytes (2674 patients), of which 64 samples (41 patients) were positive for T. verrucosum. Our data show that there was a strong influence of age on the type of lesion, with children and adults presenting more frequently with tinea capitis and skin infections, respectively (P < .0001). Infection of children and adults resulted more frequently from indirect and direct exposure to cattle, respectively (P < .01). We observed a marked increase of cases over the last 4 years, with a correlation of the number of cases and the mean annual rainfall (P < .05), suggesting that increasing humidity favors cattle infection, and thereby, human infection. Whether this increase is the consequence of climate changes remains to be determined but should be considered.