A “fungus” is a group of organisms ( or “germs”). There are some types that can cause skin problems on the surface, and there are even some types (yeasts) that normally live on the skin or in the body.
Only occasionally do those “normal” yeasts overgrow and cause skin problems. One example is Candida, which is a yeast that lives in our mouth all the way to the “other end”. It is usually in balance with other “germs” in the gut, but it can get out of balance after someone takes an antibiotic.
Overgrowth of Candida can cause “thrush” in the mouth or sores at the corners of the mouth. Candida overgrowth also causes bright red rash in body folds like under the breasts or in the groin. There are simple treatments for these conditions.
Another “yeast” that lives on the skin is especially common on the scalp and upper body. It is called Malasezzia (or Pityrosporum). Overgrowth of this yeast is associated with a condition called tinea versicolor, where there are pink, tan, or light colored splotches on the shoulders, neck, or chest. This same “normal skin yeast” has also been associated with seborrheic dermatitis, acne-like bumps, and flares of atopic eczema.
Most people think of fungus infections of the skin as things like “ringworm”, “jock itch”, “athlete’s foot”, or nail thickening. All of these are caused by a group of fungal organisms called “dermatophytes”, that can infect and live on the outer (keratin) dead skin layer.
The symptoms: itching, redness, spreading rings, or little blisters, are related to our body’s attempt to react to the fungus and try to get rid of it. Dermatophytes can be anywhere…in soil, on animals, and some types only like humans.