TITLE:
Assessment of Escherichia coli Contamination in Informal Water Sources in Kibera, Nairobi: Prevalence, Drivers, and Implications for Public Health
AUTHORS:
Teresia Nyaga, Edinah Songoro, Josiah Njeru, Susan Githii, Jedidah Kahura, Elizabeth Matey
KEYWORDS:
Escherichia coli, Water Contamination, Informal Settlements, Kibera, Public Health
JOURNAL NAME:
Open Access Library Journal,
Vol.12 No.7,
July
25,
2025
ABSTRACT: Access to clean and safe drinking water remains a major challenge in informal settlements such as Kibera in Nairobi, due to inadequate infrastructure, poor sanitation and reliance on unregulated water sources. This study assessed the prevalence of Escherichia coli (E. coli) contamination in water sources across 12 villages in Kibera and identified associated risk factors. A total of 72 water samples were collected and analyzed using the membrane filtration method. Overall, 29.2% of the samples were contaminated with E. coli, with the highest contamination rates observed in Soweto (66.7%) and Soweto West (50%). Water delivered by trucks (75.0%) and boreholes (36.0%) had higher contamination levels than public supply systems (21.0%). Samples exposed to pollution from sewage (33.0%), public toilets (50.0%), and dusty rooftops (100%) also showed elevated contamination. Additionally, untreated water sources had significantly higher E. coli levels (63.6%) compared to chlorinated samples (14.9%) (p