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Alternaria
This genus (group) contains 44 species, of which most are plant parasites, but a few are found in other environments. They are frequently soil-borne, and are commonly isolated from plants, soil, food, and indoor air environment. They are recognized as the chief fungal cause of hay fever.
Arthrinium
Arthrinium is a cosmopolitan filamentous fungus isolated from plant debris and soil. Common on dead plants, especially grasses and sedges, they are often isolated from air near grassy places in the autumn. There are no infections so far reported due to Arthrinium in humans or animals.
Aspergillus
These fungi exist worldwide, especially in the Northern hemisphere. They grow in soil, decaying vegetation, and other kinds of organic matter.
Only a few of these molds cause disease in humans. Most people are naturally immune and do not develop Aspergillosis, an Aspergillus related disease. Persons with compromised (defective) immune systems are at greatest risk of infection. Most initial infections are as a result of inhalation of spores and involve the respiratory system. Aspergillus fumigatus is the most common cause of all forms of Aspergillosis, with Aspergillus flavus being the second, and Aspergillus niger being the third. They are probably the most important contaminants of man-made and naturally occurring organic material. They are also able to produce mycotoxins when they grow as contaminants in food.
Beauvaria
Three species of Beauvaria are recognized, two of which are well known parasites of insects. B. bassiana is the most common species and is best known as the causal agent of the disastrous muscardine in silkworms. Beauveria species are occasionally isolated in the laboratory as saprophytic contaminants. It is ubiquitous in plant debris and soil. It is also isolated from foodstuff, infected insects, and the indoor air environment.
Bipolaris
The genus Bipolaris is cosmopolitan in nature and can be isolated from plant debris and soil.
It contains about 45 species, most of which are subtropical and tropical plant parasites. However, a few species are capable of causing disease in humans.
Chaetomium
This is a common fungus found in soils, dung, decaying organic matter, seeds, and wood or other cellulose-containing material, distributed worldwide. Over 100 species have been described. It is not a common pathogen in humans.
Cladosporium
Cladosporium species are widely distributed in air and rotten organic material, and are frequently isolated as a contaminant on foods. They have a worldwide distribution and are among the most common air-borne fungi. They can pose a danger indoors because they can grow in just a few days. Some 500 species have been described. It is only occasionally associated with disease in humans.
Curvularia
Most species of Curvularia are found in soil, plants, and cereals in tropical or subtropical areas, while the remaining few are found in temperate zones. It contains some 35 species, most of which are plant parasites. It can cause infections in immunocompromised hosts.
Epicoccum
Epicoccum nigrum is a cosmopolitan saprophyte (grows on decaying matter), which is commonly isolated from air, soil and foodstuff. It is also found in some animals and textiles. It is the common cause of leaf spots of various plants. It produces spores rapidly, and can grow under conditions of low humidity. It is occasionally isolated as a contaminant from clinical specimens, like skin.
Fusarium
Most Fusarium species are soil fungi and have a worldwide distribution. While most species are more common in tropical and subtropical areas, some inhabit soil in cold climates. They are found as normal mycoflora of commodities, such as rice, bean, soybean, and other crops. Some are plant pathogens, causing root and stem rot, vascular wilt and fruit rot. Other species cause storage rot and are important mycotoxin producers. Several species, notably F. oxysporum, F. solani and F. moniliforme, are recognized as being pathogenic to man and animals.
Mucor
Mucor is a filamentous fungus found in soil, plants, decaying fruits and vegetables. The genus contains 49 recognized taxa, many of which have a widespread occurrence and are of considerable economic importance. However, few species have been recovered from well-documented cases of zygomycosis (the disease caused by this organism), and infections due to members of this genus are rare.
Paecilomyces
Paecilomyces are common environmental molds and are seldom associated with human infection. However, some species, such as P. variotii, P. marquandii and P. lilacinus are emerging as causative agents of illness in the immunocompromised patient.
Penicillium
Many species of Penicillium are common contaminants on various substrates and are known as potential mycotoxin producers. They can pose a danger indoors because they can grow in just a few days. Human pathogenic species are rare, however. P. marneffei is the major pathogen in the genus, causing disease in the immunocompromised host.
Phoma
Phoma is found in soil and associated plants, particularly potatoes. It will grow on butter, paint cement and rubber. Infection from this fungus is extremely rare.
Stachybotrys
Stachybotrys is a fungus occasionally isolated as a contaminant from nature and indoor environments. The geographic distribution of Stachybotrys is wide. It has been isolated from contaminated grains, decaying plant materials, tobacco, insulator foams, indoor air, and water-damaged buildings. Stachybotrys produces mycotoxins which may lead to pathological changes in animal and human tissues. These toxins may be acquired by ingestion of food products contaminated with the fungus. They can only be produced or get airborne, however, under certain environmental settings. It is possible that Stachybotrys may play a role in development of sick building syndrome, but probably only in conjunction with other factors. In summary, what we know today is limited and speculative, and thus the health risks of environmental exposure to Stachybotrys are unclear, and its role in human disease is poorly defined.
Syncephalastrum
This is often isolated from soil and dung in tropical and subtropical regions and it can be a persistent laboratory contaminant.
Trichoderma
Trichoderma is a very common genus especially in soil and decaying wood. It lives on dead leaves, fallen timber, compost heaps, and activated sludge. It has occasionally been associated with disease in immunocompromised hosts.
Ulocladium
This species of fungus is found in soil and plant material. It is also found on dead plants, rotten wood, paper, textiles and cellulose materials. This mold frequently occurs in air and dust samples, and is also found in water damaged building materials. It has not been associated with disease in humans.
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