Large-scale data can be extremely useful in monitoring and controlling the spread of the disease, which is not always revealed by visible symptoms. In a new opinion piece submitted to Environmental science and technology, a team of researchers is now proposing a potential testing mechanism that promises to be fast, affordable and accurate: it uses a paper-based device to detect the presence of SARS-CoV-2 in wastewater.
“We have already developed a paper device to test genetic material in wastewater for proof of concept, and this offers clear potential for testing infection by adaptation,” says biomedical engineer Zhugen Yang, of the Cranfield University in the United Kingdom.
“This device is inexpensive and costs less than £ 1 [US$1.24]and will be easy for non-experts to use after further improvements. We anticipate that the device will be able to provide a complete and immediate picture of population health once this sensor is deployed. “
This research is part of an emerging field called wastewater epidemiology, or WBE. Although it has its limitations, including difficulties in extrapolating the results to a larger sample, it also has many advantages: it is non-invasive, it collects data in near real time and it is generally accurate.
The device that Yang and his colleagues propose would be folded and unfolded in stages in order to filter the nucleic acids from the pathogens of wastewater. Chemicals already added to the paper would then detect the presence of nucleic acid in SARS-CoV-2.
The result would be visible immediately – a green circle if the coronavirus was detected and a blue circle if it was not. Paper devices would be easy to stack, store and transport, and could be burnt after use.
Recent research has shown that the new coronavirus can be isolated from urine and feces, and can survive for several days outside of a living organism, and this gives scientists confidence that a wastewater test could work.
For now, this is just a concept and has not been put into practice, but it has obvious potential. In areas where SARS-CoV-2 has been detected, additional measures could be taken to minimize the spread, providing another way for health authorities to control the situation.
“In the case of asymptomatic infections in the community or when people do not know whether they are infected or not, real-time detection of wastewater in the community using paper-based analysis devices could determine whether there are COVID-19 transporters in an area to allow rapid screening, quarantine and prevention, “said Yang.
“If COVID-19 can be monitored at an early stage in a community through the WBE, an effective intervention can be taken as soon as possible to restrict movement of this local population, working to minimize the spread of pathogens and the threat to public health. “
The research was published in Environmental science and technology.