Is it Safe to Pet Stray Animals?

Cat fungus: annoying for humans and animals

What is cat fungus?

"Animal shelter closed for disinfection for several weeks", "Schools closed for one day": This is the kind of headline that people know about cat fungus from the press. Microsporum canis is the name of this contagious filamentous fungus that is spread around the world and is known medically as microsporia. Although "Canis" actually means "dog", the fungus particularly affects the skin and fur of cats. He lives from the fact that he breaks down keratin, which occurs both in the upper layers of the skin and in the hair.

"Often parents come to me with their children after a vacation trip to southern regions," explains dermatologist Dr. Angela Unholzer from Donauwörth. "It is true that the fungus can also infect domestic house tigers that are just as well-cared for, but the microsporia is particularly widespread in stray animals, which are more common in the Mediterranean region." Mammals on farms or catteries can also be infected with the highly contagious cat fungus or similar pathogens (dermatophytes). Children in particular are susceptible to the fungus, but it can also spread to adults.

Just petting infected areas of an animal's fur is often enough to cause an infection, says Unholzer. According to the expert, it is particularly tricky: You don't necessarily see the fungus in the affected animals. After contact with animals, you can clean your hands with a disinfectant that is also effective against fungal spores, thus reducing the risk of infection somewhat. But this is not a guarantee, because children in particular quickly grab other areas of skin or their hair after being stroked and thus spread the pathogens.

Symptoms of head fungus: itching, hair falling off, bald spots

If the scalp is infected (tinea capitis), the cat's fungus causes round spots where the hair breaks off just above the surface of the skin until bald areas emerge - dermatologists also refer to the phenomenon as "mown meadow". Often reddening and fine whitish flaking can also be seen on the scalp. Most of the time there is also severe itching. Yellowish blisters (pustules) rarely develop.

Body fungus symptoms: reddened area, white scales

If the fungus has infected a part of the skin on the rest of the body (tinea corporis), a reddened area with whitish scales also forms - as if it had been dusted with flour. At first it is mostly punctiform and vaguely resembles an insect bite, until it spreads to an itchy, ring-shaped reddening, possibly also with small nodules and water blisters. This is usually the stage at which those affected go to the dermatologist.

See the dermatologist as soon as possible

In addition to the symptoms, a special UV lamp, which is pointed close to the skin area in the dark, provides the first information. Then the mushroom lights up greenish-yellow, but this is not yet conclusive. The dermatologist makes the diagnosis on the basis of a microscopic examination of a hair or skin sample and the creation of a fungus culture, which takes a few weeks. At specialized facilities, the fungus can be identified quickly and reliably using molecular biological evidence of the genetic material of the pathogen.

If it is a cat fungus, all family members and pets should also be examined for possible sources of infection. In domestic animals, these look similar to those on the scalp of humans. If the relatives are not taken into account, a ping-pong effect could occur, in which people and animals close to each other repeatedly infect each other.

Therapy: antifungal agents as well as ointments and shampoos

"The fungus attacks the hair and the outer layers of the skin," says Unholzer, "which is why combination therapy is particularly important when the scalp is attacked." From the inside, antifungal agents for ingestion work against the fungi that multiply in the skin and in the follicles. Ointments, washing lotions and shampoos with suitable active ingredients fight the fungus spores on the outside. The dermatologist will explain the clinical picture and the therapy to the patient or the parents in detail. In the case of small infected areas on the body, purely external therapy may be sufficient.

Important when treating affected areas: Either wear gloves or wash and disinfect your hands immediately afterwards. Even if the areas are itchy, avoid scratching them and then touching other areas of the body. Because this is how new sources of infection easily arise.

Wash clothes and pillow cases daily

Because the fungus is quite stubborn, the therapy often takes several months. In the meantime, some hygiene measures are necessary: ​​worn clothing and used pillow cases should be washed daily at at least 60 degrees Celsius - alternatively, special detergents with disinfectants can also be used at lower temperatures. Affected children should, depending on the severity of the infection, temporarily stay away from kindergarten or school in consultation with their doctor.

The fungus can settle in hair shafts and hair follicles for a long time. That is why dermatologists do not stop the treatment until hair samples have tested negative several times in a row. As long as the therapy continues: complications or permanent consequences are usually not to be expected. However, if you ignore the symptoms for a long time and start treatment too late, you may risk permanent bald spots.