The house dust mite is a pyroglyphid that lives in human habitation. Dust mites feed on organic material, such as flakes of shed human skin, and flourish in the stable environment of dwellings. House dust mites are a common cause of asthma and allergic symptoms worldwide. The mite’s gut contains potent digestive enzymes that persist in their feces and are major inducers of allergic reactions such as wheezing. The mite’s exoskeleton can also contribute to allergic reactions.

Airborne bacteria can be present in air or on surfaces, usually appears in buildings with poor ventilation, poor maintenance or as a result of water damage