The Higher Institute of Health (ISS) gave the news. The discovery refers to a study, being published, carried out through the analysis of waste water collected in times prior to the manifestation of Covid in Italy: the samples taken in the purifiers of urban centers in northern Italy, in the Turin area the Castiglione plants and Collegno, have been used as a “spy” of the circulation of the virus in the population.
In particular, the Turin samples were supplied to the ISS by Smat, the Turin Metropolitan Water Company, which has been conducting a study with the Institute, starting from last October, aimed at identifying the presence of enteric viruses in the drinking water supply chain. Another game compared to Covid. But the company’s availability of frozen specimens was instrumental in detecting coronavirus as well.
“An intriguing discovery that opens up to unexpected speculation – reflects Professor Giovanni Di Perri, head of infectious diseases at the Amedeo di Savoia hospital in Turin -. Who knows: maybe it was a small outbreak, then aborted. Or maybe the incipt of the epidemic, then undercover. ” Assumptions, for now. «It is an excellent result to have allowed ISS to monitor the virus in the periods prior to the declared pandemic – comments Paolo Romano, President of Smat -: a job that our Research Center was able to carry out thanks to the accreditation of its laboratories» .
Certainly it is news that casts new shadows on a whole series of factors: including the high rate of pneumonia cases recorded last autumn in Northern Italy, which was judged anomalous by doctors with respect to the flu trend.
«Since 2007 with my group we collect and analyze samples of waste water taken at the entrance of purification plants – explains Giuseppina La Rosa of the Water Quality and Health Department of the ISS Environment and Health Department, who led the study with Elisabetta Suffredini, Department of Food Safety, Nutrition and Veterinary Public Health -. The study examined 40 samples collected from October 2019 to February 2020 and 24 control samples for which the sampling date (September 2018-June 2019) made it possible to safely exclude the presence of the virus “.
The results, confirmed with two different methods, showed the presence of SARS-Cov-2 RNA in the samples taken in Milan and Turin on 18 December 2019 and in Bologna on 29 January 2020. In the same cities positive samples were also found in the following months of January and February, while the samples of October and November 2019, as well as all the control samples, gave negative results.
«In perspective, a surveillance network in the area can be invaluable in controlling the epidemic “, explains Luca Lucentini, director of the Water Quality and Health Department. There is still a lot to learn about Covid.