A dust mite allergy is an allergic response by the human body to the presence of dust mites, which are tiny eight-legged insects that commonly live in close proximity to humans. The allergy is actually not a reaction to the dust mite itself, but rather to dust mites’ fecal pellets, sometimes called frass. A single fecal pellet from a dust mite measures about 20 microns across, and contains proteins which certain people are allergic to.
The fecal pellets that trigger a dust mite allergy, unlike pollen or pet dander, are heavier than most allergens, and tend not to travel very far from their source. They are therefore most bothersome to the allergy sufferer when he is near a mattress, pillow, or other place where dust mites live in large numbers. Symptoms of a dust mite allergy include sneezing, watery eyes, runny nose, and other symptoms common to most nasal allergies. About one person in every ten suffers from a dust mite allergy. Most antihistamines and other allergy drugs will reduce or eliminate symptoms.
Those who suffer from a dust mite allergy can also control the source of the problem to some extent. Frequent laundering of textiles and bedding is very effective in eliminating dust mites from these places. A simple washing gets rid of most of the detritus left behind by mites, and washing in hot water will kill most of the mites as well. Using a household dryer after a wash cycle will kill virtually all mites that may have survived the washing machine.
Dust mites thrive in environments where humans are present. This is mainly because they feed on particles of organic matter, such as small flakes of dead human skin. Each of us sheds enough skin to support a rather large population of dust mites in our home, making the presence of household dust mites almost universal. They are most common in the summer, since warm temperatures and high humidity are most conducive to their survival. In very warm climates, they can live comfortably year-round.
For all the annoyance they can cause, dust mites cannot bite or carry diseases. A person with a dust mite allergy in addition to asthma, however, needs to take special care to limit his exposure to dust mites. The highly sensitive airways of an asthma sufferer can become constricted in the event of an allergic reaction to dust mites, leading to additional symptoms which can be dangerous, depending on the degree of control the person has over his asthma.