Scientists in the United Kingdom (UK) and India have now come together to jointly develop a low-cost sensor to detect the SARS-CoV-2 virus, that causes the infectious coronavirus disease (Covid-19), within the wastewater. This is expected to help several middle-to-low-income countries that are struggling to control the prevalence of Covid-19 in a larger area where it is often spread through wastewater.
The sensor was tested with wastewater collected from a sewage treatment plant in Mumbai spiked with SARS-Cov-2 Ribonucleic Acid (RNA). The researchers found that the sensor was able to detect the genetic material at concentrations as low as 10 picograms per microlitre.
The low-cost sensor to detect Covid-19 was developed by researchers from the University of Strathclyde in the UK and those from the Indian Institute of Technology (IIT) Bombay in India. “Many low- to middle-income countries face a challenge in tracking Covid-19 in people because of limited access to the necessary facilities for mass testing,” said Dr. Andy Ward, chancellor’s fellow in the department of civil and environmental engineering. “Looking for traces of the virus within wastewater would enable public health officials to get a better understanding of how prevalent the disease is in a larger area,” he added.
How does the Covid-19 sensor work to detect SARS-Cov-2 within wastewater?
The sensor developed jointly by UK and Indian scientists can be used with portable equipment that uses the standard Polymerase Chain Reaction (PCR) test to detect the SARS-CoV-2 virus. This eliminates the need for the expensive chemicals and lab infrastructure needed for real-time quantitative PCR tests, according to the research published recently in the journal, Sensors and Actuators B: Chemical.
Explaining the importance of the technique, Dr. Ward said, “the current gold-standard method of real-time PCR testing (qPCR) requires expensive laboratory equipment and skilled scientists to complete. Furthermore, if resources are limited, testing of human samples would most likely take precedence over wastewater epidemiology surveillance. Therefore, lower cost, alternative approaches are required in order to support wastewater surveillance,” he said.
The importance of testing wastewater for the presence of SARS-CoV-2
According to Dr. Ward, the testing of wastewater for the presence of SARS-CoV-2 nucleic acid is already widely recognized as a tool to identify areas where the case numbers are likely to be increasing and therefore allow more targeted action to be taken to limit the viral spread in specific regions.
Adding to his inputs, Dr. Siddharth Tallur, associate professor in the department of electrical engineering at IIT Bombay, said, “The method we have developed is not just applicable to SARS-CoV-2, it could be applied to any other virus so it’s very versatile.” He added that in the future, the focus will be on optimizing the assay further to increase accuracy and integrate it with a portable platform to handle “both PCR reaction and electrochemical measurement”.
(With inputs from PTI)