Aspergillus is a species of fungus that is composed of filaments and is present in mold. It is found in soil, grains, foods, and rotting compost. Its spores are present in the air and in dust, and may be ingested through the consumption of fruit. Approximately 185 species of aspergillus exist and they can be harmful to humans, causing mycosis
, or aspergillosis
, an infestation of respiratory passages that is potentially fatal.