fungal infection, infection caused by a fungus (see
Fungi Fungi , kingdom of heterotrophic single-celled, multinucleated, or multicellular organisms, including yeasts, molds, and mushrooms. The organisms live as parasites, symbionts, or saprobes (see saprophyte).
..... Click the link for more information. ), some affecting animals, others plants.
Fungal Infections of Human and Animals
Many fungal infections, or mycoses, of humans and animals affect only the outer layers of skin, and although they are sometimes difficult to cure, they are not considered dangerous. Athlete's foot and ringworm ringworm or tinea , superficial eruption of the skin caused by a fungus, chiefly Microsporum, Trichophyton, or Epidermophyton.
..... Click the link for more information. are among the common superficial fungal infections. Fungal infections of the mucous membranes are caused primarily by Candida albicans (see candidiasis candidiasis , infection of the mucous membranes caused by the fungus Candida albicans. Other terms for candidiasis are yeast infection, moniliasis (after a former name of the fungal genus), and thrush, the latter term usually being reserved for infection of
..... Click the link for more information. ). It usually affects the mouth (see thrush thrush, in medicine, infection caused by the fungus Candida albicans, manifested by white, slightly raised patches on the mucous membrane of the tongue, mouth, and throat. The mucous membrane beneath the patches is usually raw and bleeding.
..... Click the link for more information. ) and the vaginal and anal regions.
The fungi that affect the deeper layers of skin and internal organs are capable of causing serious, often fatal illness. Sporotrichosis is an infection of farmers, horticulturists, and others who come into contact with plants or mud. The disease affects the skin and lymphatic system and, in rare cases, becomes disseminated. Blastomycosis is caused by a yeastlike fungus that reproduces by budding. The North American variety, caused by Blastomycosis dermatitidis, occurs more often in men and seems to be limited to the central and E United States and Canada. Wartlike lesions appear most often on the skin, sometimes spreading to the bones and other organs. The South American variety of blastomycosis is caused by B. brasiliensis. Chytridiomycosis, caused by Batrachochytrium dendrobatidis, is a deadly fungal skin infection in amphibians, which it kills by damaging to the animals' normally permeable skin, thus disrupting the transport of air and moisture.
Among the fungi that infect the deeper tissues is Coccidioides immitis, which causes coccidioidomycosis coccidioidomycosis , systemic fungus disease (see fungal infection) endemic to arid regions of the Americas, contracted by inhaling dust containing spores of the fungus Coccidioides immitis.
..... Click the link for more information. , sometimes called valley fever, a lung infection that is prevalent in the SW United States. Cryptococcosis is another fungus disease that may be localized in the lung or disseminated, especially to the central nervous system. It has a worldwide distribution, affecting men twice as often as women. The causative agent (Cryptococcus neoformans) has been isolated in pigeon excretions. Histoplasmosis, which is caused by spores of the fungal genus Histoplasma, is a severe infection that shows varied symptoms. In acute cases ulcers of the pharynx and enlargement of the liver and spleen are present. In other forms tubercularlike lesions of the lung occur. In its benign form no symptoms may be present.
Fungal infections sometimes follow the use of antibiotics, which kill nonpathogenic as well as pathogenic bacteria bacteria [pl. of bacterium], microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. Once considered a part of the plant kingdom, bacteria were eventually placed in a separate kingdom, Monera.
..... Click the link for more information. , thereby providing a free field in the body for fungal invasion. Opportunistic fungal infection occurs when a fungus enters a compromised host, as in the case of such diseases as AIDS AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, and neurological disorders.
..... Click the link for more information. . Treatment for fungal infections includes systemic antifungal agents, such as amphotericin B amphotericin B , antibiotic that halts the growth of several disease-causing fungi. Discovered in 1956, it is produced by bacteria of the genus Streptomyces.
..... Click the link for more information. , fluconazole, and itraconazole, and agents usually used topically, such as clotrimazole (Lotrimin) and miconazole (Monistat).
Fungal Infections of Plants
Serious damage is done to crops each year by fungal infections of plants such as smuts smut, name for an order of parasitic fungi (Ustilaginales) and the various diseases of plants caused by them. Smuts produce sootlike masses of spores on the host.
..... Click the link for more information. , rusts rust, in botany, name for various parasitic fungi of the order Uredinales and for the diseases of plants that they cause. Rusts form reddish patches of spores on the host plant. About 7,000 species are known.
..... Click the link for more information. , ergots ergot , disease of rye and other cereals caused by the fungus Claviceps purpurea. The cottony, matlike body, or mycelium, of the fungus develops in the ovaries of the host plant; it eventually turns into a hard pink or purple body, the sclerotium, or ergot,
..... Click the link for more information. , and mildews mildew, name for certain fungi and protists, for the diseases they cause in various crops, and for the discoloration (and sometimes the weakening and disintegration) they cause in such materials as leather, fabrics, and paper.
..... Click the link for more information. . Dutch elm disease, a disease that has seriously depleted the number of elm elm, common name for the Ulmaceae, a family of trees and shrubs chiefly of the Northern Hemisphere. Elm trees (genus Ulmus) have a limited use as hardwoods for timber, especially the rock or cork elm (U. thomasi).
..... Click the link for more information. trees in the United States, is caused by the fungus Ceratostomella ulmi. Such diseases are usually fought with fungicides fungicide , any substance used to destroy fungi. Some fungi are extremely damaging to crops (see diseases of plants), and others cause diseases in humans and other animals (see fungal infection).
..... Click the link for more information. or by developing resistant plants. See also diseases of plants diseases of plants. Most plant diseases are caused by fungi, bacteria, and viruses. Although the term disease is usually used only for the destruction of live plants, the action of dry rot and the rotting of harvested crops in storage or transport is similar
..... Click the link for more information. .