Abundance of Pathogenic Escherichia coli Virulence-Associated Genes in Well and Borehole Water Used for Domestic Purposes in a Peri-Urban Community of South Africa.

In the absence of pipe-borne water, many people in Africa, especially in rural communities, depend on alternative water sources such as wells, boreholes and rivers for household and personal hygiene. Poor maintenance and nearby pit latrines, however, lead to microbial pollution of these sources. We evaluated the abundance of and the prevalence of pathogenic virulence genes in water from wells, boreholes and a river in a South African peri-urban community. Monthly samples were collected between August 2015 and November 2016. In all, 144 water samples were analysed for using the Colilert 18 system. Virulence genes (, , , , , , , ) were investigated using real-time polymerase chain reaction. Mean counts ranged between 0 and 443.1 Most Probable Number (MPN)/100 mL of water sample. Overall, 99.3% of samples were positive for at least one virulence gene studied, with being the most detected gene (81/140; 57.6%) and the gene the least detected gene (8/140; 5.7%). Both intestinal and extraintestinal pathogenic genes were detected. The detection of virulence genes in these water sources suggests the presence of potentially pathogenic strains and is a public health concern.