Fungal infections usually itch. Those due to zoophilic (animal) fungi generally produce a more intense inflammatory response with deeper indurated lesions than fungal infections due to anthropophilic (human) species. Some lesions, usually those on the trunk, have a prominent scaling margin with apparent clearing in the centre. Hence the name "ringworm".
Children below the age of puberty are susceptible to scalp ringworm and anthropophilic fungi (from humans) have become common in some inner city areas. They can also be infected with zoophilic fungi (from animals), particularly cattle, dogs, and cats. Cattle ringworm can cause an intense inflammatory response in children, producing a "kerion" described below. They rarely develop anthropophilic fungal infection.
Adults. From adolescence onwards infection of the feet is a common occurrence. Tinea cruris in the groin is seen mainly in men and fungal nail infections (onychomycosis) have become particularly common.
Infection from dogs and cats with a zoophilic fungus (Microsporum canis) to which humans have little immunity can occur at any age. A patient returned from a skiing holiday with intensely itchy "eczema", which refused to clear. A stray kitten, mewing outside in the dark, had been taken indoors, warmed in their sleeping bags, and infected the whole party with M. canis.
Was this article helpful?