The house dust mite is a guest in human habitation. Dust mites feed on human waste such as flakes of shed human skin and hair cells. They thrive in a stable environments such as the home. Dustmites and the highly allergenic particles found in their feaces are a major cause of allergy sensitive conditions and aggravate other allergies not directly caused by Dustmites. Dustmite allergy is a hypersensitive reaction to proteins in the excretion of Dustmites.

House dust mites are a common cause of asthma and allergic symptoms worldwide. The mite’s gut contains potent digestive enzymes (notably proteases) that persists in their feces and are major inducers of allergic reactions such as wheezing. The mite’s exoskeleton can also contribute to allergic reactions. The European house dust mite (Dermatophagoides pteronyssinus) and the American house dust mite (Dermatophagoides farinae) are two different species, but are not necessarily confined to Europe or North America; a third species Euroglyphus maynei also occurs widely.