Dust Mites

What Are Dust Mites?

Dust mites are very small, insect-like pests that feed on dead human skin cells and thrive in warm, humid settings. Dust mites are too small for us to see. They are not parasites that bite, sting or burrow into our bodies. Instead, people who are allergic to dust or dust mites are reacting to inhaling proteins in dust that comes from dust mite feces, urine or decaying bodies. Any swelling (also called inflammation) of the nasal passages caused by dust mites is considered a dust allergy.

Dust Mite Sources

Dust mites are common and can be found in almost every home. About 4 out of 5 homes in the United States have dust mite allergens in at least one bed. Dust mites can live in bedding, mattresses, upholstered furniture, carpets and curtains. These places collect skin flakes from people and pets, which are the main food source for dust mites.

Humidity is the biggest factor that affects dust mite levels in a home. Dust mites do not drink water. Instead, they absorb moisture from the air. When indoor air is very dry, dust mites cannot survive.

Unlike pet allergens, dust mite allergens usually do not stay in the air for long. They settle quickly into dust, bedding, carpets and other fabrics. The allergens build up in the same places where dust mites live. Because people spend many hours in bed, most exposure to dust mite allergens happens while sleeping.

How Dust Mite Allergens Affect Health

Dust mites are one of the major indoor triggers for people with asthma.

Ongoing exposure to dust mites at home can impact the health of people with asthma and those who are allergic or sensitive to mites. These allergens can trigger mild to severe allergic symptoms and can be responsible for asthma attacks. Up to 85% of individuals with asthma have an allergic reaction to dust mites that make their asthma worse. A mild case may cause an occasional runny nose, watery eyes and sneezing. In severe cases, the condition is ongoing, resulting in persistent sneezing, cough, congestion, facial pressure or even a severe asthma attack. People with asthma who are sensitive to dust mites face an increased risk of asthma attacks.

How to Protect Against Dust Mites

You can take action to reduce dust mites in your home.

• Reduce humidity. Keep your home below 50 percent humidity. Keep your home below 50 percent humidity. Use a simple, inexpensive hygrometer to measure your home’s humidity. Simple ways to reduce indoor humidity include using a dehumidifier, turn on bathroom exhaust fans after bathing/showering and repairing leaks and water damage promptly. In humid areas, air conditioning and dehumidifiers can help to draw moisture out of the air. 
• Reduce the places where dust mites can live. Remove upholstered furniture or use furniture with smooth surfaces. Remove drapes and curtains. Reduce clutter, stuffed animals, and other places where dust mites live. If that’s not possible, wash stuffed animals weekly in hot water (at least 120 degrees) to kill and wash away dust mites.
• Reduce dust mites in bedding. Cover mattresses and pillows with allergen encasements. Wash bedding in hot water (at least 120 degrees F) once a week to kill and wash away dust mites.
• Replace carpets. Carpeting should be replaced by hard-surfaced flooring, especially if occupants are allergic to dust mites. If you must keep the carpet, use a vacuum cleaner with a HEPA (High-Efficiency Particulate Air) filter weekly. Damp clean floors often, focusing on catching dirt and dust without wet mopping.
• Dust regularly. Dust regularly to reduce the amount of dust and improve overall indoor air quality in your home. When dusting, use something that can trap and lock dust (like a damp washcloth or microfiber cloth) dust to reduce the amount of it that is stirred up when cleaning.

People with allergies to dust mites or with asthma triggered by dust mite allergies need to reduce dust mites in their home.

Learn about dust mites and how to minimize exposure in the home in the video below.