As the name suggests, these mites are usually found in house dust, and they thrive on dead skin cells shed by humans. So, they tend to colonize beds, mattresses, upholstered furniture, clothes, rugs, and carpets. As dead skin cells are found abundantly in the above said locations, they don't have to bite humans. Otherwise too, dust mites do not bite humans. In fact, the itchy, red skin rash that is often called dust mite bites, is an allergic reaction to the proteins in the fecal matter of these mites.