Several fungi cause diseases in humans, some of them serious. For example, a disease of the lungs and spinal cord is caused by a fungus called Cryptococcus neoformans. This disease is serious in AIDS patients, and it is often spread in dust by air currents.
Another human pathogen is Candida albicans. This organism causes disease of the oral cavity (thrush), as well as yeast disease of the reproductive tract. Normally the disease is mild, but in people infected with HIV, for example, it can be serious.
Other human fungal diseases include ringworm and athlete’s foot. Each is caused by fungi of various genera, and each is characterized by blisterlike regions on the skin or in the webs of toes or fingers. Fungal diseases of the lung tissues include histoplasmosis, blastomycosis, and coccidioidomycosis.