An Outbreak of Trichophyton quinckeanum Zoonotic Infections in the Czech Republic Transmitted from Cats and Dogs

Trichophyton quinckeanum, a zoophilic dermatophyte mostly known as the causative agent of rodent favus, is relatively rarely reported to cause human infections. Indeed, no infections were detected in Czechia between 2012 and 2015 despite routine verification of species identification by ITS rDNA sequencing. By contrast, 25 human and 11 animal cases of infection were documented from December 2016 to December 2020 and the rates tended to grow every following year. Interestingly, most of the cases were reported in the Olomouc region, suggesting a local outbreak. We bring the evidence that human T. quinckeanum infections are most commonly contracted from infected cats or, less frequently, dogs. Although rodents or contaminated soil and environment could be the source of infection to cats and dogs, the occurrence of infections in multiple animals in the same household suggests direct transmission among animals. Confirmation of the identification by molecular methods is highly recommended due to morphological similarity with T. mentagrophytes/T. interdigitale. Antifungal susceptibility testing of isolates to eight antifungals was performed using EUCAST methodology (E.Def 11.0). Among the tested antifungals, terbinafine, amorolfine, ciclopirox and efinaconazole were most potent in vitro and elevated minimum inhibitory concentrations were obtained for fluconazole and ketoconazole.

The presence of dermatophytes in infected pets and their household environment

ABSTRACT The aim of this study was to diagnose dermatophytosis in pets and investigate the presence of dermatophytes in their home environment. Samples from hair coat were collected from 70 pets: 47 dogs, 19 cats, three guinea pigs and one rabbit. After mycological culture, 188 samples were collected from the household environments in 26 homes: 78 from places were of predominantly used by the tutors, 66 from places used by the animals, 44 from flooring, and 24 samples from contactees. Samples were seeded on Mycosel agar, incubated at 25°C, and the colonies were identified by their macro-and-microscopic characteristics. Dermatophytes were found in 37.1% of the samples originating from the sick animals. Microsporum canis was the most prevalent species, isolated in 12 dogs and eight cats; Trichophyton quinckeanum in three guinea pigs, Microsporum gypseum in two dogs and Trichophyton mentagrophytes in one cat. Dermatophytes were found in 69.2% of the surveyed homes; 29.5% of the places/objects predominantly used by the tutors, 42.4% mainly used by the animals, 31.8% from floors, and 50% from contactees. The meeting of dermatophytes in animals and in the household environment confirms the possibility of transmission by direct or indirect contact and their importance in public health.