The study of house dust mites in Taiwan
Chang, Y.C.; Hsieh, K.H.
Annals of Allergy 62(2): 101-106
1989
ISSN/ISBN: 0003-4738 PMID: 2919796 Document Number: 346680
By using a radioallergosorbent test (RAST) and intradermal skin testing, our previous studies strongly suggested that house dust mites are the most important allergen in Taiwan, especially in asthmatic children. This study was conducted to determine the distribution of house dust mites in houses of mite-sensitive asthmatic children and normals, the species of mites in various house dust samples, the seasonal prevalence, and the relation between the content of mite allergen and the mite density in dusts. Serial samples were collected every month between February 1986 and January 1987 from 61 houses of mite-allergic patients and nine normals. About 1 m2 surface area each of (A) family couch, (B) TV room floor carpet, (C) mattress, and (D) bed room floor carpet was vacuumed for one minute. The flotation method was used to collect mites in dusts and mites were counted under an inverted phase contrast microscope. Identification of house dust mite species was also performed. The RAST inhibition method was used for assay of mite allergen in dust extracts. The results showed the following six points. (1) Dermatophagoides pteronyssinus (DP) was the dominant species found in house dust in the Taipei area (78.8%). (2) The mean number of mites was greater in August though November and lowest in July. (3) The content of mite allergen did not correlate with the number of mites in dust sample. (4) The average number of mites in patients' houses was not different from that in normals' houses. (5) The age (time used) of furnitures had no effect on the number of mites. (6) The size of skin reactivity to dust extract had no relation to the number of mites in dust sample. Thus, the mites were present similarly in houses of both asthmatic children and normals, and the development of house dust mite allergy in asthmatic children may be due to aberrant immunoregulatory function.