SARS-CoV-2 has been circulating in northern Italy since December 2019: Evidence from environmental monitoring

摘要: Abstract Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is responsible for the coronavirus disease COVID-19, a public health emergency worldwide, and Italy among most severely affected countries. The first autochthonous Italian case of COVID-19 was documented on February 21, 2020. We investigated possibility that SARS-CoV-2 emerged in earlier than date, by analysing 40 composite influent wastewater samples collected - framework other wastewater-based epidemiology projects between October 2019 2020 from five treatment plants (WWTPs) three cities regions northern (Milan/Lombardy, Turin/Piedmont Bologna/Emilia Romagna). Twenty-four additional same WWTPs September 2018 June (i.e. long before onset epidemic) were included as ‘blank’ samples. Viral concentration performed according to standard World Health Organization procedure poliovirus sewage surveillance, with modifications. Molecular analysis undertaken both nested RT-PCR real-rime assays. A total 15 positive confirmed methods. earliest dates back 18 December Milan Turin 29 January Bologna. Virus ranged below limit detection (LOD) 5.6 × 104 genome copies (g.c.)/L, (23 out 26) quantification PCR. Our results demonstrate already circulating at end 2019. Moreover, it different geographic simultaneously, which changes our previous understanding geographical circulation virus Italy. study highlights importance environmental surveillance an early warning system, monitor levels population identify outbreaks even cases are notified healthcare system.