Zoonotic Potential of Dermatophytosis in Small Mammals

Abstract

Zoophilic dermatophytes play an important role in animal and human health. Small exotic mammals can be infected with a variety of dermatophytes that inhabit the fur, skin, nails, environment, cage, and/or soil. Humans are susceptible to these organisms; however, younger or immunocompromised individuals and people with intensive contact with pets are particularly susceptible to infection. The most important dermatophytes for small mammals are Trichophyton mentagrophytes, Trichophyton erinacei, Trichophyton quinckeanum, Arthroderma benhamiae, Arthroderma vanbreuseghemii, Microsporum gypseum, and Microsproum persicolor. Dermatophytes elicit a host inflammatory response, pruritus, which results from a cell-mediated hypersensitivity to fungal wall antigens. Erythema, excoriations, crusts, hyperkeratosis, alopecia, and secondary bacterial dermatitis are common clinical findings. In small mammals, infection can be self-limiting and serious consequences are relatively rare. A definitive diagnosis is primarily achieved through external physical examination, Wood’s lamp examination, direct microscopy of tape preparations and skin scrapings, and microscopic visualization of conidia after culture. Effective therapy for dermatophyte infection includes topical application of appropriate antifungal drops, sprays or spot-on products, bathing (e.g., enilconazole, clotrimazole, and miconazole), and parenteral antifungals (e.g., itraconazole and griseofulvin). To prevent reoccurrence or new infections, appropriate veterinary examination and quarantine of every new animal and appropriate treatment of affected small mammals and their environments are advised. Veterinarians should also inform local health authorities, pet shop employees, their staff, and especially hedgehog handlers about dermatophyte infection risks.