PARASITIC RELATIONSHIP BETWEEN MICROSPORUM-CANIS AND THE CAT

Cats are often cited as reservoirs of M. canis but it is questionable whether M. canis is part of the resident flora of the cat's skin and h air or only a transient organism. Studies indicate that M. canis is mo st often isolated from cats at risk of infection or exposure from othe r infected cats or from a contaminated environment. Many more cats are culture-positive for M. canis than have dermatophytosis. Culture isol ation alone is not an indication of dermatophytosis; the diagnosis of dermatophytosis requires microscopic evidence of infection as well as culture evidence of the presence of the dermatophyte. The cat's hair c oat adopts the culture image of its surroundings. Diverse factors may influence the frequency of isolation of M. canis. Nevertheless, isolat ion of M. canis implies either active disease or fomite carriage and w arrants aggressive investigation of the clinical situation.