Investigation of Fungal Contamination in the Environment of Intensive Care Units of a Tertiary Care Hospital: Research Article

Abstract

Fungi are unicellular and multicellular eukaryotic organisms that can be found ubiquitously in soil, water and air. Their profound ability to live in multiple temperature ranges and places is attributed to their ability to produce pathogenic or non-pathogenic spores. Spores are resilient enough to withstand routine cleaning and disinfection practices. Presence of pathogenic spores in hospital environment, particularly in intensive care units, is critical in terms of immunocompromised patient safety who are being treated in such premises. Keeping in view the potential hazardous nature of fungi and their spores, the present study aimed to determine and identify different species of fungi responsible for air and surface contamination of the medical intensive care unit (MICU) and pediatric intensive care unit (PICU) environment and surfaces. For this, 70 samples from air and other surfaces (bed rails, instrument trays, floor and walls) were collected at MICU and PICU over a period of 1.5 months. Air samples were collected using the passive settle plate method, whereas samples from surfaces were collected using sterile swabs. Swabs were inoculated onto Sabouraud agar plates by the spread plate method and were incubated at 30-37 °C for 24 hours to 1 week, and were continuously observed to see the growth. Fungal growth on plates ensured fungal presence at that site. To identify the obtained fungal genera, growth cultures were examined for their morphological characteristics and then examined microscopically using the slide culture method. Slides were examined under the microscope for specific fungal microscopic structures. A total of 54 samples (77.14%) showed significant fungal growth, whereas 16 samples (22.85%) showed no growth. Among positive fungal samples, eight different types of fungi such as Neurospora, Candida spp, Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Fusarium, Rhizopus and Mucor sp. were observed to be involved in contamination of surfaces and air of MICU & PICU.  Relative to PICU, the MICU environment had increased fungal contamination as percentages of positive samples were 35.71% and 41.42% for PICU and MICU, respectively. The most abundant fungus recorded in both of the ICUs was Neurospora sp., followed by Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Candida spp., Fusarium, Rhizopus and Mucor species, with 30%, 24.28%, 11.42%, 10%, 7.14%, 7.15%, 5.71% and 2.85% relative percentages, respectively. Furthermore, the most contaminated site was observed to be the wall, followed by air, instrument tray, floor and bedrail, respectively. Presence of pathogenic fungal species in the environment of ICUs indicates the urgent need for stringent measures, particularly for the protection of resident immunocompromised patients of ICUs.