Assessment of Airborne Fungal Spores in a tertiary care hospital in South Western Nigeria

Abstract

TPS 752: Respiratory effects and allergies, Exhibition Hall, Ground floor, August 27, 2019, 3:00 PM - 4:30 PM Background/Aim: Increasing evidences show that exposure to indoor fungal spores has resulted in increased prevalence of hospital-acquired infections. This study aimed to determine the burden of airborne fungi species in the indoor environments of a tertiary hospital in South Western Nigeria. Methods: Air samples were collected in the dry (January–April) and raining (June-September) seasons from four categories of wards viz; surgery (8 wards), obstetrics/gynecology (5 wards), medical (8 wards) and paediatric (6 wards). Air samples were collected using a two-stage Anderson sampler at a flow rate of 15L/min for 15 minutes in the morning (8:00-11:00) and evening (13:00-16:00) hours over a 3-day period. A total of 966 air samples were cultured each on Potato-dextrose agar (PDA) and Sabouraud-dextrose agar (SDA) and incubated at 25°C for 7-10 days. Total fungi count (TFC) was presented in colony-forming unit per cubic meter (CFU/m3) and compared to recommended concentration of fungal spores in hospital air (≤ 25CFU/m3). Analysis was performed using t-test and ANAOVA at p<0.05. Results: Majority, 930 (96.3%) and 934 (96.7%) of the samples were positive for fungi on PDA and SDA respectively. In both seasons, the paediatric wards recorded the highest mean TFC on PDA (dry:38.33 ± 30.41CFU/m3; raining:44.78 ± 40.16CFU/m3,p<0.05) and SDA (dry:48.22 ± 33.17CFU/m3; raining:52.00 ± 36.76CFU/m3) while the surgery wards had the least TFC on PDA (dry:28.40 ± 21.37 CFU/m3; raining:32.77 ± 29.95CFU/m3) and SDA (dry:42.70 ± 19.44 CFU/m3; raining:39.44 ± 29.61CFU/m3). The mean TFC in each ward was above the recommended concentration of 25CFU/m3. The most frequent occurring fungal species was Aspergillus spp. constituting about 30.5% of the total isolates. Conclusions: This study revealed high fungal contamination in the wards. The presence of Aspergillus spp. pose great threat to immunocompromised patients. Therefore, periodic survey and efficient ventilation system are necessary to prevent possible hospital-acquired infections.