I. Characteristics of asthma caused by dust mites: 1. High incidence in spring and autumn (peak of mite reproduction). 2. Symptoms often appear earlier than 2 years old. 3. Nocturnal attacks are common. Second, mites are most closely related to the development of asthma, and 70% to 80% of children with asthma are allergic to mites. Mites live around humans and feed on the dander shed by humans. The most suitable living conditions for mites are temperature of 22-26OC and relative humidity of more than 55% (Xiamen is a paradise for mites to grow and breed because the temperature and humidity meet the above conditions all year round). Mites are the number one relevant factor for allergic diseases in humans. The main allergic diseases caused by dust mites are: inhalation asthma, allergic rhinitis, and allergic eczema. Anti-mite measures include: a. Rooms are not carpeted b. Mattresses, pillows and quilts should be wrapped up, preferably with mite resistant fabrics, and pillows must be replaced every 1 to 2 years. c. Bed sheets, blankets, curtain cloth should be washed with hot water (55`c or more) every week to kill mites. d. Vacuum cleaner can be used to sweep the dust in your home (note that the quality should be good so as not to become a mite raising machine). e. Children should not play with soft, hairy toys, which are most likely to grow mites, or wash such toys with hot water once a week, or freeze them at low temperature once a week. f. Do not use fabric sofas at home, furniture is best made of wood, leather or plastic. g. Use dehumidifiers or air conditioners to keep the humidity in your home below 50% (humidity below 50% is difficult to survive and reproduce). h. Do hygiene only when children are not indoors, because the flying dust contains mite secretions, excretions or crusts, and all parts of them are strong allergens regardless of whether the mites are dead or alive. i. Acaricides: Application is not recommended because they cannot penetrate deep into the lint or pillow insert and have poor acaricidal effect, and such chemical acaricides are not good for children’s health.