The body normally hosts a variety of germs, including bacteria and fungi. Some of these are useful to the body, some produce no harm or benefit, and some can cause harmful infections.
Some fungal infections are caused by fungi that live on the hair, nails, and outer skin layers. They include yeast-like fungi such as Candida.
In cutaneous candidiasis, the skin is infected with Candida fungi. This type of infection is fairly common. It can involve almost any skin on the body, but most often it occurs in warm, moist, creased areas such as the armpits and groin. The fungus that most often causes cutaneous candidiasis is Candida albicans.
Candida is the most common cause of diaper rash in infants. The fungi take advantage of the warm, moist conditions inside the diaper. Candida infection is particularly common in people with diabetes and in those who are obese. Antibiotics, steroid therapy, and chemotherapy increase the risk of cutaneous candidiasis. Candida can also cause infections of the nails, edges of the nails, and corners of the mouth.
Oral thrush, a form of Candida infection of the moist lining of the mouth, usually occurs when people take antibiotics. It may also be a sign of an HIV infection or other weakened immune system disorders when it occurs in adults. Individuals with Candida infections are not usually contagious, though in some settings people with weakened immune systems may catch the infection.
Candida is also the most frequent cause of vaginal yeast infections. These infections are common and often occur with antibiotic use.
People with seriously weakened immune systems and cutaneous candidiasis may go on to develop more serious Candida infections inside their body.