Coronavirus in wastewater: discovery could lead to early warning system
As reported by the Bloomberg news agency, Dutch scientists have detected coronaviruses in Amersfoort's wastewater - and that's even before the first infections were reported there in the town southeast of Amsterdam. This suggests that the wastewater could serve as an early warning system for the COVID-19 disease.
As reported today by Swiss radio and television SRF, Eawag, the water research institute of the ETH Domain, has also been studying wastewater for the development of an early warning system since the first day of dissemination of Sars-VoV-2:
On February 24, it became known that the first person in Ticino had contracted an infection with the novel coronavirus. On the same day, the research team led by Christoph Ort started its work. Since then, the nine largest wastewater treatment plants in Ticino have taken a one-liter water sample every day, says the Eawag environmental engineer, "Now we already have more than 300 samples stored in our freezers."
The Swiss researchers are confident that they will not only succeed in detecting the virus in water, but that it can also be quantified. Ideally, it would still be possible in 2020 to estimate approximately how many people are infected with Sars-CoV-2. However, this would require an official, Switzerland-wide measurement system. According to Eawag, a Sars-CoV-2 early warning system would require a network of 19 large wastewater treatment plants distributed throughout Switzerland.
This would provide information on the excretions of 2.5 million people in Switzerland.
How does the virus get into the wastewater?
An infected person excretes the virus in their stool. According to the study, the rapid spread of the virus will also increase the amount in sewage systems. However, microbiologist Gertjan Medema and his colleagues at the KWR Water Research Institute in Nieuwegein tell the business magazine that it is unlikely that sewage will become a major route of transmission of the disease. Bloomberg.
Wastewater monitoring as an early warning system possible?
"It is important to collect information on the occurrence and fate of this new virus in wastewater to understand if there is no risk to wastewater workers, but also to determine if wastewater monitoring could be used to monitor the circulation of Sars-CoV-2 in our communities," Medema also said in a published report.
He added, "This could complement current clinical surveillance, which is limited to covid 19 patients with the most severe symptoms." Indeed, researchers have long suspected that the number of unreported cases of coronavirus infection is far higher than can be confirmed through testing.
The Dutch researchers' report is the first on the detection of Sars-CoV-2 in wastewater, they also said. However, wastewater monitoring already works in monitoring other viruses, such as poliovirus. For example, wastewater can serve as an early warning system for the emergence and reemergence of the coronavirus in cities, the scientists explained.
Rapid tests already developed
British and Chinese scientists have also made use of this knowledge. They have developed a rapid test that can detect coronaviruses in wastewater. As scinexx reports, Zhugen Yang of Cranfield University in the United Kingdom and his colleagues at the Chinese Academy of Sciences want to use it to determine whether there are covid patients in an area and thus quickly enable further testing, quarantine and other countermeasures.
