Background: Swimming pools are contaminated with different microorganisms. This study aimed to investigate the fungal contamination of the swimming pools and detect the susceptibility of the isolated fungi to routinely used disinfectants.Methods: Surface and water samples were collected from different parts of 13 indoor swimming pools. Isolated fungal species were identified based on respective colony morphology, microscopic examination, and RFLP-PCR. Susceptibilities of fungal species to common disinfectants used in swimming pools were investigated, according to M38-A and M27A3 protocols.Results: Of the 795 collected specimens, 2211 isolates from 35 fungal species were identified. The most isolated fungi were filamentous hyaline hyphomycetes (especially Aspergillus spp.), and dematiaceous (especially Cladosporium spp.), followed by Mucorales, Candida species and dermatophyte species. The most contaminated places were shoes changing and dressing rooms. Sodium hypochlorite (bleach) and chloroxylenol (Dettol) were found to be effective against all isolated fungi after 2.5 and 5 minutes, respectively. Isopropyl alcohol (Afrooz disinfectant solution) was not an effect on Aspergillus spp., dematiaceous fungi, and Candida spp. after 10 minutes’ exposure. The efficacy of hydrochloric acid (liqueur de Javel) showed the most fungicidal activity against dermatophytes at all times. Conclusions: For efficient cleaning, the disinfectant must remain on the surfaces for an appropriate period. Sodium hypochlorite was efficient antifungal activity in a shorter time for killing all species of fungi. Given the different sensitivity and resistance profile of fungi to disinfectants, regular assessment of the disinfectants used for cleaning the pools is suggested.

Background: Catalase enzyme is a potential virulence factor for Aspergillus species. Objectives: This study aimed to evaluate the catalase activity in conidium and mycelium of Aspergillus flavus and A. fumigatus isolated from environmental and clinical samples. Methods: Forty Aspergillus species (20 A. fumigatus and 20 A. flavus) were evaluated. Species were identified using the macroscopic and microscopic criteria of the isolates on culture media and the PCR-RFLP method, using the MwoI enzyme. The activity of the enzyme was evaluated using the Amplex red catalase assay kit. The Shapiro Wilk, Kolmogorov-Smirnov, Mann-Whitney, and Wilcoxon Signed Rank tests were used to analyze the data. Results: The mean conidial and mycelial catalase activities in A. flavus clinical and environmental isolates were 58.10, 57.80 mU/mL, and 1328.30, 531.60 mU/mL, respectively. In A. fumigatus clinical and environmental isolates, the activities were 61.10 and 61.40 mU/mL, and 1248.90 and 722.90 mU/mL, respectively. A significant difference was found between conidial and mycelial catalase activity in Aspergillus species (P = 0.01). The mycelial catalase activity of Aspergillus species isolated from clinical samples was higher than the environmental ones (A. flavus P = 0.01 and A. fumigatus P = 0.04). Conclusions: The mycelial catalase activity was higher than conidia. Clinical isolates of A. flavus had similar mycelium activity to A. fumigatus. By using the information provided in the present study, the severity of aspergillosis can be predicted, which paves the way for identifying new antifungal agents.