E. coli

Escherichia coli

Anup Ghimire, Rock Face Limited

Common Microbes in Drinking Water

• Cryptosporidium• Anabaena species• Copepods• Rotifers• E. coli• Rhizopus stolinifer• Naegteria fowleri• Legionella Pneumophila• Chaetomium species

• Salmonella Enterica

E. Coli

• Pathogenic bacteria found in the digestive tract of human and animal.

• Sub group of faecal coliform bacteria

Sources in drinking water

Human induced sources • Failing septic tanks,• leaking sewer lines• wastewater treatment plants• combined sewer overflow (CSOs)• urban storm water runoff

…sources in drinking water

Animal sources• Manure spread on land• Livestock in runoff or in streams• Improperly disposed farm animal wastes• Pet and bird wastes

Coliform Test

• Biological quality tested by total coliform test• Absence of coliform bacteria: safe drinking water• Presence of coliform bacteria: contaminated water

Health Effects

• Abdominal cramps and diarrhoea• Cellular function such as protein synthesis, mitochondrial

function, cytoskeletal function, cell division, ion secretion, transcription and apoptosis.

Categories of E. coli

• enteropathogenic E.coli (EPEC)• entrohaemorrhagic E. coli (EHEC)• enterotoxigenic E. coli (ETEC)• enteroaggregative E. coli (EAEC)• enteroinvasive E. coli (EIEC)• diffusively adherent E. coli (DAEC)