Assessment of microbiological contaminants in community water sources in lower Nyakach Division, Kisumu County, Kenya

Abstract

The importance of water as a vehicle for spreading diseases has long been recognized and many studies have demonstrated the relationship between illness and deficiencies in water supply and sanitation. This study was conducted between October 2008 and July 2009, to determine microbiological water contaminants and related human health problems in community water sources in Lower Nyakach division, Kisumu County. Water samples were collected in selected water points, analyzed using membrane filter technique and their level of microbiological contamination determined using Escherichia coli type I as bio-indicator. Household level surveys and key informant interviews were conducted and secondary data obtained from Pap-Onditi district hospital on cases of environmental and human health risks associated with water contamination. Data from field samples and survey were analyzed usingthe Statistical Package for Social Sciences. Multiple comparisons between sites were made by Analysis of Variance (ANOVA) and the student t-test. Statistical significance was assessed at p ≤ 0.05. The mean counts for faecal coliforms were lower than that of total coliforms in all samples in both dry and rainy seasons although the mean counts total coliforms were higher during the rainy season than the dry season. Water samples from water impoundments showed significant differencesin total coliforms compared to recommended WHO levels and no significant differences for faecal coliforms (α = 0.05). Water samples from shallow wells showed significance difference for faecal coliforms between three sampling sites (Pap-Onditi, Urudi and Bonde). From the survey and hospital findings typhoid fever and amoebic dysentery were the most common water-borne diseases in the study area. Faecal contaminated water possesses high human health risks which are responsible for the reported increased water-borne diseases. The study concludes that total and faecal coliforms are important parameters in monitoring faecal contamination and water quality in the area. Most of the community water sources are seasonal and largely contaminated. Consequently, frequent monitoring of water quality and levels of contaminants using total and faecal coliforms is recommended at common water points to curb potential health related risks.