Italian researchers have found the traces of the new coronavirus or COVID-19 in the wastewater collected from Milan and Turin in December 2019, suggesting that that coronavirus was already spreading in the Northern part of Italy ahead of China reporting the first case.

The Italian National Institute of Health studied 40 sewage samples that got collected from the wastewater treatment plants located in the northern part of Italy between October 2019 and February 2020. An analysis that was released late on Thursday stated that the samples taken in Milan and Turin on December 18 showed the presence of the novel deadly virus.

"This research may help us understand the beginning of virus circulation in Italy," Giuseppina La Rosa, an expert in environmental wastewater at the Italian National Institute of Health who co-led the research, said in a statement detailing the findings.

Study Claims COVID-19 Was There in December

Coronavirus
A worker of Junjiang Industrial Limited Company arranges disposable surgical gowns in Yilong New District at Bouyei-Miao Autonomous Prefecture of Qianxinan in southwest China's Guizhou Province, Feb. 21, 2020. Medical supply companies in Yilong New District have been producing medical supplies at full capacity to support the fight against the novel coronavirus, or COVID-19. (Xinhua/Yang Wenbin/IANS) Xinhua/IANS

Small studies conducted by scientific teams in the Netherlands, France, Australia and elsewhere have found signs that the virus that causes COVID-19 can be detected in sewage, and many countries are beginning to use wastewater sampling to track the spread of the disease.

La Rosa said the detection of traces of the virus before the end of 2019 was consistent with evidence emerging in other countries that COVID-19 may have been circulating before China reported the first cases of a new disease on Dec. 31.

A study in May by French scientists found that a man was infected with COVID-19 as early as December 27, nearly a month before France confirmed its first cases. La Rosa said the presence of the virus in the Italian waste samples did not "automatically imply that the main transmission chains that led to the development of the epidemic in our country originated from these very first cases".

Samples positive for traces of the virus that causes COVID-19 were also found in sewage from Bologna, Milan and Turin in January and February 2020. Samples taken in October and November 2019 tested negative. The institute said it plans to launch a pilot study in July to monitor wastewater at sites identified in tourist resorts.

(With agency inputs)