Microsporum is a fungal genus which is most famously responsible for ringworm, a fungal infection which can be observed in both humans and animals. Microsporum canis is a particularly well known species in this genus, although several other species are also linked with ringworm and other skin problems, in some patients. Microsporum can be carried on cats, dogs, and other animals, and the fungus also grows readily on media such as rice and sugar.
In nature, a colony of microsporum tends to be flat, with a spreading growth habit and a white to creamy color, depending on the species. Microsporum colonies have a soft, wooly texture, and the colony tends to acquire a grooved appearance over time. When cultured in the lab, the fungi can grow on several different growth media.
These fungi are capable of penetrating the hair and skin, where they can grow to create distinctive lesions associated with ring worm. Someone with a microsporum infection will have small reddish disc-shaped markings where the fungi grow, and these markings can spread and start to blur together other time. Eventually, the markings will develop crusts, which can ooze and turn bloody. Hair above the area of the lesion will fall out, due to damage caused by the fungal colonization. While these lesions are present, the patient can pass on fungal spores to others. Ringworm infection is an especially common problem in kennels, where one animal can pass it to the whole kennel, and infected animals can keep reinfecting each other.
Treatment for microsporum infection involves administering antifungal drugs. Oral medications can be taken, and the site can also be cleaned with antigfungal soaps which will kill the fungi so that they cannot spread. Eventually, normal skin and hair will grow back, concealing all traces of the infection. Antifungal dips are also available, and may be used on small animals, with the animal being briefly dunked in a prepared dip to eliminate all fungus from the body.
In rare cases, people can be infected with microsporum but not develop lesions. In these cases, they are still capable of passing the fungus on to others and may not be aware of the infection they carry. If members of a household find that they keep getting ringworm, it may be advisable to test all human and animal occupants for signs of a latent infection to see if someone is acting as a reservoir for the fungi.
