Comparison of airborne fungal flora in indoors and outdoors of Zabol city in spring and summer

Introduction: As one of the organisms contaminating the air, fungi can cause many diseases such as superficial diseases, opportunistic and systemic infections, important allergic reactions, hypersensitivity, etc. Given the importance of diseases caused by airborne fungi, this study aimed to compare airborne fungal flora of indoors and outdoors in Zabol city in spring and summer. Materials and Methods: In this descriptive, cross-sectional study, samples were collected by the active method using 540 plates containing Sabouraud dextrose agar medium with chloramphenicol from indoors and outdoors of five districts in Zabol city during spring and summer. For identification, fungal colonies were cultured on slides and the results were analyzed using Fisher's exact test. Results: In this study, Aspergillus fumigatus and Mucor were the most prevalent types of fungal flora found indoors and outdoors in spring and summer. Mucor had the highest fungal concentration (cfu: 312.85) found indoors in spring and the lowest fungal concentrations belonged to Absidia and Cladosporium (cfu: 165.15). In spring, A. fumigatus and Absidia presented the highest (cfu: 285.29) and the lowest (cfu: 165.15) outdoor fungal concentrations, respectively. In summer, the highest indoor fungal concentrations were recorded for A. fumigatus and A. flavus (cfu: 265.45) and the lowest levels belonged to A. nidulans, Rhizopus, and Mycelium (cfu: 165.15). A. fumigatus (cfu: 285.45) and Scopolaris (cfu: 165.15) respectively presented maximum and minimum outdoor fungal concentrations. In general, the highest indoor and outdoor fungal concentrations belonged to A. fumigatus and Mucor, and the lowest levels were recorded for Absidia and Cladosporium in spring. In summer, A. fumigatus and A. flavus had the highest indoor and outdoor concentrations, and the lowest fungal concentrations were found for A. nidulans, Rhizopus, Mycelium, and Scopolaris. Total concentration of fungal flora was inversely related to temperature and wind speed, but it had a direct relationship with humidity. Thus, the average humidity (24%) was higher in spring than that in summer (15%). Conclusion: The results demonstrates that the air of Zabol city contains a variety of fungal spores. As fungi can induce various diseases in humans and are also important causes of pathogenicity and mortality in immunocompromised individuals, identifying the diversity of fungal flora in different places and introducing the environmental fungal flora to infectious disease specialists, dermatologists, doctors, and so on will help in the prevention, treatment, and reduction of mortality due to diseases caused by human contact with fungi.