Dust Mites

Overview

More than 50% of the US population test positive to one or more allergens. The most common allergens are cockroaches, dust mites, ragweed, pet dander, peanuts and seasonal pollens such as Bermuda grass, Russian thistle, and White oak. Substantially reducing exposure can help reduce clinical symptoms of the allergy or asthma. A significant number of asthma and allergy sufferers are allergic to dust mites and controlling mites plays an important role when adopting an allergen avoidance strategy. The house dust mite is found in pillows, mattresses, upholstered furniture, carpets, and drapes and while other allergens are seasonal, dust mites can easily have a permament residence in your house and care must taken to reduce their presence.

For those with a dust mite sensitivity, it is important to attempt to reduce their presence in the home. One study showed that for those whose asthma has gone into remission by the age of 18, those with dust mite sensistitivity are more likely to experience a relapse with the return of their asthma by the time they reach 26. It follows then that dust mite avoidance and/or reduction should be a part of a management program for continuuing the state of remission of asthma.

What are dust mites?

Dust mites belong to the arachnid family and are thus related to spiders. They are microscopic and not visible to the naked eye (less than .3 mm). They are found normally in most households and the most common location is in the bedroom and in beds. The reason for this is simple: dust mites feed on flakes of human skin--the skin which you normally and naturally shed when you simply move around at night in bed and shed flakes of dead skin. This means the dust mites live in sheets, covers, blankets, and pillows. An average bed could have upwards of 1.5 million dust mites! They need moisture to survive and more will be found in temperate climates than in dry climates. It is their droppings that is the cause of allergic and asthmatic reactions in individuals

Preventive measures

What are some preventive measures that can be taken to control house dust mites? Washing sheets and pillowcases frequently in hot water. The use of impervious mattress covers such as mattress encasings which go over pillowcases, mattress pads, sheets, and blankets, have been shown to be effective in reducing dust mite allergens by significant amounts (up to 87%) and this has also resulted in improved peak flow. Morning peak flow is an asthma related measurement that reflects how well a person’s asthma is under control.

One study showed that dust mites tend to not survive in an unmade bed. What happens is that dust mites need moisture to live and take in water through glands located on the outside of their body. An unmade bed will then allow for the sheets and mattresses to air out and dry, thereby depriving the dust mites of the moisture necessary for them to survive.

Removing carpets is a possible preventive measure in order to help eliminate dust mites and other allergens that can be trapped in the carpet hairs.