Samples of wastewater from the Paris sewage system have been showing traces of COVID-19 again since the end of June, having vanished when France imposed a lockdown, according to the head of the laboratory leading the research. Infection rates in France are subsiding, but officials this week made the wearing of masks in enclosed public spaces compulsory after a series of localised flare-ups. To date COVID-19 has killed over 30,000 people in France.
Early studies by scientists in The Netherlands, France, Australia and elsewhere suggest sewage sampling for signs of the SARS-CoV-2 coronavirus could help estimate the number of infections in a geographic area, without having to test every person. Laurent Moulin, who heads the research laboratory run by public water utility company Eau de Paris, cautioned the findings on their own did not mean a resurgence of the virus in the population since France eased its lockdown restrictions.
“We had the lockdown, which reduced the number of sick people, and then a little while later we saw a reduction of the concentration of SARS-CoV-2 in the waste water,” Moulin said, referring to the strain of virus behind the COVID-19 epidemic. “What are we seeing since the end of June? We’ve seen some locations that were negative (for virus traces) and are becoming positive,” he said. Infection rates in Paris are declining in line with the national trend.
Source: Reuters
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