Background: The purpose of this study was to investigate the presence, frequency and comparison of Aspergillus spp. in nasal cavity and bedroom of healthy volunteers and patients with allergic rhinitis. Materials and Methods: In this cross-sectional study, a group of patients with allergic rhinitis (N=50) were selected based on positive skin prick test. Healthy volunteers were chosen to be in the comparison group by matching in age, gender, and no history of respiratory system disease. Samples from nasal cavity and different parts of bedroom were collected and cultured. Cultured Aspergillus spp. was identified by standard mycological techniques. Results: The most common species isolated from all samples of healthy volunteers was A. flavus (88%), followed by A. niger (76%) and A. fumigatus (74%). A. flavus (56%) was the predominant species isolated from all samples of patients, followed by A. niger (34%) and A. fumigatus (6%). Conclusion: A. flavus was the most prevalent species of Aspergillus both healthy volunteers and patients. The presence of Aspergillus in homes does not necessarily imply a cause and effect relationship with illness, but we speculate that A. flavus may be a major source of aeroallergens along with A. niger and A. fumigatus; and should alert physicians and healthcare professionals to do more vigorous environmental testing.

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