Asymptomatic carriage of Microsporum canis in the cat

Microsporum canis is the main causative agent of feline ringworm. This cosm opolitan, zoophilic and zoonotic dermatophyte can be isolated from the hair coat of cats without apparent clinical lesions. This " asymptomatic carriag e " can signify either a true asymptomatic infection either a transient mec hanical carriage. In the first case, the cat is infected, contagious and mu st be treated. In the second case, the cat is not infected but must be simp ly considered as a source of indirect transmission of the fungus just like a contaminated environment and treatment is not always justified. The patho physiological mechanisms involved both in asymptomatic infection and mainte nance of the mechanical carriage remain poorly understood. Recent studies i n this field, especially at the molecular level, are exposed in this review .