Chennai: Researchers of Italy’s National Institute of Health, testing 40 water samples collected from sewage treatment plants in cities of Milan and Turin from October 2019 to February 2020, found coronavirus presence that dated as early as December 2019. The first cases of local spread in Italy were reported only in February.
Reuters quoted Noel McCarthy, an expert in population evidence and technologies at Britain’s Warwick Medical School, as saying the detection of SARS-Cov-2 genetic material in Italian wastewater was “reliable evidence of cases of Covid-19 being present there at that time”.
Rowland Kao, an epidemiology and data professor at Scotland’s Edinburgh University, however told the agency that this finding does not, on its own, tell us if “that early detection was the source of the epidemic in Italy, or if that was due to a later introduction into the country”.