P363 Mycoflora diversity in stored water from selected households in nairobi

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Introduction: Water is a very vital natural resource for all life on earth as it is used widely. Water plays an important role in the world economy, the uses can be categorized into; commercial use where it is used in hostels, restaurants, offices, and other commercial activities. Fungi are ubiquitous in nature; they produce spores that are small-sized, able to stay airborne for a long duration, and transported over long distances during air dispersal. These are major sources of allergens and airway irritants that are detrimental to health. Biofilms in water distribution systems and storage containers provide favorable habitat for microorganisms as they accumulate better in solid-liquid interfaces that enable them to be embedded in the gelatinous matrix of extracellular polymers excreted by the microorganisms leading to resistance of microbes from environmental stresses. Fungi hydrophobicity and adaptability have enabled them to assemble and colonize different surfaces in domestic settings. The potential health effects caused by fungi in treated water are still not well highlighted and thus the need to carry out this study to investigate the mycoflora isolated from stored water. Methods This was a cross-sectional study conducted from 2019-2021, whereby 120 water samples were collected from stored containers in households in Nairobi county Kenya. The fungal strains were plated onto Sabouraud's dextrose agar (SDA), Potato Dextrose Agar, and Czapecks Agar media with chloramphenicol (0.05 mg/mL) (Oxoid, U.K.). The plates were incubated for 7 days at 25°C. Fungal identification was done by direct microscopy and morphological features. Results A total of 101 fungal species were isolated from water samples. Yeasts 48 (47.5%), Rhodotorula 34 (33.6%) accounted for the unicellular fungi. Among Filamentous mycoflora, the most common isolated fungi were Aspergillus species 13(12.8%), followed by Fusarium spp 4 (3.9%) with Mucor and |Rhizopus species accounting for 1 (0.9%) respectively. Yeasts species were the most common species isolated from water species and Aspergillus species were more frequently isolated from filamentous fungi. Conclusion Yeasts species were the most common species isolated from water species and the roles they play in biofilm needs to be further investigated.