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bioRxiv · 10.1101/731778

Development and evaluation of a rapid on-site water pathogen detection system for water quality monitoring

Chia, J. Y.·Tay, Y. P.·Poh, D.·Tay, B. H.·Koh, E.·Teo, J.·Yap, J.·Lim, M.·Soh, L. T.·Lee, Y. K.·Lee, C.-L. K.
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Abstract

Timely response to outbreak of water-borne diseases caused by bacteria requires efficient monitoring and rapid detection strategies. Herein, we report a rapid DNA-based on-site detection system for specific detection of Pseudomonas aeruginosa. To evaluate the test performance of our method against spiked water samples, parallel tests based on real-time PCR and standard culture methods were concurrently performed. Test sensitivities of between 96.7% and 92.3% were obtained, based on the calculation obtained from qPCR and culture test, respectively, with a corresponding level of specificity of 92.9% and 83.3%. Time-to-result is around 45 min, with a detection limit of 1 CFU/100 mL. Here, a fully-deployable detection method where bacteria of-interest can be detected rapidly with high accuracy was described. This test method can be modified to detect other bacteria of-interest and can also be used in different applications. The test results can be obtained on-site and can therefore be particularly useful in public facilities health surveillance, where regulators can quickly determine if a site is safe or if other emergency response measures are required.\n\nIMPORTANCEPseudomonas aeruginosa is a well-established water quality biomarker, known to be associated to humans health risks. To ascertain the presence of this pathogen, relevant stakeholders currently rely on standard quantitative ISO methods (APHA 9213E) which require 6 days from sampling to results. This window could potentially lead to waterborne outbreaks if the contaminated water features are not shut down for proper and urgent mitigation. This manuscript describes a method to detect this disease-causing microorganism in its viable forms under 1 hour, with a sensitivity of 1 CFU/100mL. Besides providing valuable information of the quality of water system, this direct monitoring of pathogens can reduce substantial time needed from sampling to reporting. This method can be established as a platform technology for other pathogenic microorganisms. On-going work to develop economic point-of-care prototypes could facilitate quick screening of targeted waterborne pathogens and results in better assessment of public health risk and quick in devising emergency response measures and other management strategies.

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Chia, J. Y., Tay, Y. P., Poh, D., Tay, B. H., Koh, E., Teo, J., Yap, J., Lim, M., Soh, L. T., Lee, Y. K., Lee, C.-L. K.. 2019-08-10. Development and evaluation of a rapid on-site water pathogen detection system for water quality monitoring. https://doi.org/10.1101/731778

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