Background & Aims:
Asthma is a chronic lung condition that affects individuals of all ages. House dust mites (HDM), which belong to various species within the family Pyroglyphidae, are commonly found in household dust. This study aimed to assess HDM at the homes of asthmatic patients and a control group in
South Khorasan Province, Birjand, Iran.
Materials and Methods: This case-control study involved ۱۰۰ asthma patients and ۱۰۰ clinically healthy individuals. The mean age of the study participants was reported as ۳۰.۱±۵.۱ years. Dust samples were collected from the living rooms and bedrooms using a vacuum cleaner and were then examined both directly and through flotation methods. Afterward, the samples underwent molecular analysis for diagnostic confirmation. Statistical analysis was conducted using SPSS software (version ۲۷) through the Chi-square test to evaluate the relationships between the study variables and the abundance of HDM.
Results: In total, ۶ (۳%) out of ۲۰۰ samples were found to be infested with HDM. Moreover, HDMs were found in ۵ samples from asthma patients and just ۱ sample from healthy individuals. The majority of asthma patients who tested positive for mites resided in rural areas, experienced insufficient sunlight, had mites present in their bedrooms, and used handmade carpets. The results showed a significant difference between the study variables (e.g., residency, sample sites, and type of carpet) and HDM abundance (P<۰.۰۵). In this study, ۱۰۰ patients with allergic asthma were examined, with the majority being under ۲۰ (۳۵%) years old. Both morphological and molecular analyses confirmed that all isolated samples were identified as Dermatophagoides pteronyssinus.
Conclusion: The current study revealed a markedly low presence of mites in the dust samples from both asthmatic and control subjects, a finding that contrasts significantly with earlier studies conducted in Iran. Important factors linked to the prevalence of HDM included residence in rural areas, limited sunlight exposure, and the use of handmade carpets.
