Waste Water Analysis in Europe Advances Covid 19 Pandemic Two / Three Months Before Fist Cases Reported
Sunday, June 21, 2020 – 7:02 UTC
The coronavirus was already present in the two major cities of northern Italy in December, more than two months before the first case was detected, a national health institute for the study of waste, water has find.
Researchers discovered genetic traces of Sras-CoV-2 – as the virus is officially known – in wastewater samples taken in Milan and Turin late last year, and in Bologna in January , the institute’s ISS said in a statement.
Italy’s first known native case was discovered in mid-February.
“The results help to understand the beginning of the circulation of the virus in Italy,” the ISS said.
They also “confirm the now international consolidated evidence” of the strategic function of sewage samples as an early detection tool, he added.
Italy is the first European country to be affected by the virus and the first in the world to impose national locking. The first known case, other than a couple visiting Chinese tourists, was a patient in the town of Codogno in the Lombardy region.
On Feb 21, the government designated Codogno a so-called red zone and sentenced it to closed shutters, followed by nine other cities in Lombardy and Veneto. In early March, he extended the stop across the country. Italy has registered more than 34,500 deaths.
ISS water quality experts Giuseppina La Rosa and his team examined 40 waste water samples from October 2019 to February 2020.
The results, confirmed in two different laboratories, by two different methods, showed the presence of SARS-CoV-2 in the samples taken in Milan and Turin on December 18, 2019 and in Bologna, on January 29, 2020.
Samples from October and November 2019 were negative, showing that the virus had not yet arrived, La Rosa said.
The data were in line with the results obtained from the retrospective analysis of samples from hospitalized patients in France, which found positive cases for SARS-CoV-2 dating from the end of December, the institute said.
He also pointed to a recent Spanish study that found genetic traces in the waste water samples taken in mid-January in Barcelona, about 40 days before the first indigenous case was discovered.
Since the start of the epidemic, researchers around the world have been tracing the spread of the coronavirus through water and wastewater, to find genetic traces of Brisbane in Paris and Amsterdam.
Given the large number of coronavirus cases that have few or no symptoms, waste water testing is seen as a way to report the presence of the virus even before the first cases are clinically confirmed in the affected areas by the epidemic, or where it has decreased.
The ISS said it had urged the health ministry to coordinate the collection of samples regularly in sewers and at the entrance to sewage treatment plants, “as a tool to detect and monitor the circulation of the virus in the different territories, at an early stage ”.
This is the launch of a pilot study on priority sites identified in tourist resorts in July, and a nationwide installation of the wastewater monitoring network is expected by fall.