Fungal Spore Air Pollution: Seasonal Concentration, Diversity and Antifungal Resistance in Nairobi City County, Kenya
| dc.contributor.author | Kipchumba, Kiprop Vincent | |
| dc.date.accessioned | 2026-03-11T09:35:17Z | |
| dc.date.available | 2026-03-11T09:35:17Z | |
| dc.date.issued | 2025-11 | |
| dc.description | A Thesis Submitted in Partial Fulfillment for the Award of the Degree of Master of Science in Medical Microbiology in the School of Pure and Applied Sciences of Kenyatta University, November, 2025 Supervisor: 1.Anthony Kebira Nyamache 2.Christine Bii | |
| dc.description.abstract | Poor air quality is associated with cardiovascular and respiratory diseases including, allergies, obstructive lung diseases, cancer, and even reduced life expectancy. According to WHO data, approximately 92% of the global population is exposed to air pollution, causing up to 6.5 million mortalities. Understanding and subsequent management of microbial air pollution have been a main focus for research. Several studies have reported various effects of Particulate matter (PM10) on human health. However, limited information is available on the effects of airborne fungi on human health. Studies focusing on evaluating fungal air quality in urban environments to identify biological health risks and provide necessary information for control are limited. This work aims to determine fungal diversity and concentrations in the atmospheric air of Nairobi, Kenya, towards determining fungal air quality. Nonrandomized sampling design was adopted, where sampling sites were categorized into 4 zones: (1) Traffic zones, i.e., roundabouts and major roads; (2) Commercial zones; (3) Recreation zones; Waste dumping zones. A total of 384 samples were collected; out of these, 192 samples were collected during the dry season (January to March), remaining 192 samples were sampled during wet seasons (June to July). Temperature, humidity, and wind speed data were recorded using the Accuweather mobile Application. The identified fungal isolates were enumerated using the Omelyansky formula (2013). Culture-dependent techniques were adopted for fungal identification and characterization. Moreover, their potential pathogenicity was tested by subjecting the isolates to temperature tolerance, hemolytic, and protease tests. Antifungal susceptibility tests were performed using the CLSI M38-A2 broth microdilution method against 3 azole antifungals; [fluconazole (FCZ), voriconazole (VCZ), and itraconazole (ITZ)], which are commonly dispensed antifungals. The relationship between the fungal concentration and meteorological parameters was analyzed using multiple regression and Pearson correlation. The wet season had the highest number of fungal spores (5318.88 CFU m− 3 ) compared to the dry season (1929.58 CFU m− 3 ). Consequently, we identified 502 isolates across two seasons; 16 genera and 38 species comprising Ascomycota 426(89.31%), Basidiomycota 21(4.40%), Deuteromycota 17(3.56%), Muromycota 7(1.47%) and Zycomycota 6(1.26%). The most isolated fungal species included Candida (17.13%), followed by Penicillium 66(13.15%), Fusarium 62(12.35%), Aspergillus 61(12.15%), and, Cladosporium 60(11.95%). Temperature, humidity, and windspeed significantly affected airborne fungal concentration (p=.000), (p=.0280), and (p=.000), respectively. Pearson correlation analysis showed that temperature negatively correlated with the fungal concentration significantly (p=.000). Humidity had significant positive correlation with fungal concentration (p=.001) while the wind speed negatively correlated with the fungal concentration significantly (p=.000). A total of 33/58(56.89%) fungal displayed growth at 37°C. Extracellular proteases production was evident in 15/58(25.86%) isolates. After hemolysis, 12(20.69%) isolates were capable of beta (complete) hemolysis, 39(67.24%) showed alpha (partial) hemolysis and 7(12.07%) displayed gamma or no hemolysis. Among the characterized isolates, most of the airborne fungal isolates tested were susceptible to voriconazole and itraconazole. However, resistance against fluconazole was observed among 4/18 (22.22%) of all the isolates tested. Therefore, our findings provide insightful information about the concentration of airborne fungi in relation to human activities, location in relation to weather patterns in Nairobi. It highlights the significance of fungal spore pollution antifungal resistance and their significance in the burden of respiratory conditions and climate change | |
| dc.description.sponsorship | SIDA grant number 274.846/Distomos/001 | |
| dc.identifier.uri | https://ir-library.ku.ac.ke/handle/123456789/32701 | |
| dc.language.iso | en | |
| dc.publisher | Kenyatta University | |
| dc.title | Fungal Spore Air Pollution: Seasonal Concentration, Diversity and Antifungal Resistance in Nairobi City County, Kenya | |
| dc.type | Thesis |