A paper device to rapidly detect E. coli in environmental water

Project Status: 

A CSIR developed lateral flow device that rapidly detects Escherichia coli (E. coli), has been successfully tested in the field at the Tshwane (Daspoort) Waste Water Treatment Works. The presence of E. coli in water sources indicates sewage contamination, which could pose severe health risks if contaminated water is consumed.

Field tests were carried out to validate the developed device against current gold standard methods such as membrane filtration to assess the functionality and capability of the test to be used as an early warning system. The system is aimed at providing waste water treatment facilities with rapid (same day) results to prevent the discharge of effluent into rivers that do not meet green drop standards. Discharged effluent of poor water quality not only places strain on the environment and a scarce natural resource, but also increases the risk for spread of diseases through waterborne contaminants. The slow turn-around time in obtaining results for water testing affects service delivery and the operational management of water treatment plants. 

Bacterial and viral pathogens have been classified as one of the key factors decreasing water quality in South Africa. The World Health Organization reported that anually, two million deaths worldwide are attributed to unsafe water, improper sanitation and lack of hygiene. Therefore, microbial hazards have been identified as the main challenge in the delivery of safe drinking water.

Current methods for detecting pathogens in water are neither simple nor portable. They require 18 - 24 hours of incubation of the sample at constant elevated temperature, are time consuming (usually requiring 1 to 5 days), expensive and require well equipped laboratories employing trained technicians to carry out routine tasks. Water sampled from lesser serviced areas is transported to fully equipped laboratories, which are usually centrally located, for testing. In some instances, this water reaches the laboratory facility 2 to 3 days after sample collection at the site.  

ColiSpot addresses the shortcomings of traditional techniques by reducing the total detection time for E. coli and negating the need for a fully equipped laboratory.

Contact Person

Kevin Land

Key Concept

Escherichia coli
Escherichia coli is a gram negative bacterium of the genus Escherichia. Although most strains are harmless, some serotypes are pathogenic and can cause food poisoning, clinically manifested as nausea, vomiting and bloody diarrhea. The organism is transported and spread through contaminated food and water sources through the fecal oral route. Harmless serotypes form part of the natural flora of the mammalian gut and is always present in feces, for this reason E. coli has been classified as a direct indicator of sewage contamination.