Dust mites are tiny arthropods that are commonly found in human dwellings and are difficult to detect with the naked eye, and are responsible for allergic asthma, rhinitis and dermatitis. They are mainly found in pillows, bedding, upholstery and furniture. Dust mite excretions, secretions and decomposition products of dead insects are allergens, and through activities such as making beds and cleaning houses, the dust flies and hypersensitive reactions are generated after inhalation by allergic people. Prevention and treatment methods are as follows: 1, indoor ventilation, adequate sunlight, indoor relative humidity control at 50% or less. Can use high-performance dehumidifiers and air conditioners, to frequently clean or replace the air conditioner dust cover. 2. Clothes are often exposed to the sun, and mattress covers, quilt covers and pillowcases made of mite resistant materials are used. Clothes bedding, etc. washed once a week with hot water greater than 55 ℃ can kill mites and remove most mite allergens. Dryer drying should be greater than 55℃ for more than 10 minutes. Also can be frozen at -17℃~-20℃ for at least 24 hours (such as in the cold winter clothes on the balcony, small items can be placed in the refrigerator), after freezing to wash to remove dead mites and related allergens. 3, carpets, curtains and home soft decorations should be diligently replaced and cleaned, no carpets in humid areas, use blinds, vinyl or leather cushions, wooden furniture is good. 4, good personal hygiene, do not keep pets. Desensitization treatment of dust mite allergy is safe and effective, generally after the age of 4 years can be treated, the younger the age the better the effect. Chemical mite killing has limited effect.