Italian researchers are claiming that the novel coronavirus was circulating in northern Italy as early as September 2019, well before the initial COVID-19 outbreak in Wuhan, China.
A study by the National Cancer Institute in Milan published over the weekend by its Tumori Journal found that 11.6 percent out of 959 volunteers who took part in a lung cancer screening trial between September 2019 and March 2020 developed COVID-19 antibodies before the first case was confirmed in the country on February 21, the Reuters news agency reported.
Follow-up research by the University of Siena showed that four people had developed antibodies as early as the first week of October, meaning they were infected in September, the report said.
The earliest cases of the virus being detected in humans date back to November 2019 in Wuhan, where the virus has been thought to have possibly originated at a local live animal market.
Italy was one of the first countries besides China to experience a severe outbreak, with hospitals overloaded and deaths mounting in March in the northern region of Lombardy before distancing restrictions curbed the virus’s spread.
The World Health Organization, which has previously said that the possibility that the coronavirus had been secretly circulating outside of Wuhan “cannot be ruled out,” said Monday that it was in contact with the study’s authors “to discuss and arrange for further analyses of available samples and verification of the neutralization results.”
Giovanni Apolone, a co-author of the study, told Reuters that the main finding was that “people with no symptoms not only were positive after the serological tests but also had antibodies able to kill the virus. It means that the new coronavirus can circulate among the population for a long time and with a low rate of lethality, not because it is disappearing, only to surge again.”
The new findings come after Italian researchers in March told Reuters they had detected an uptick in severe pneumonia and flu cases in Lombardy in the last three months of 2019, further indicating that the respiratory virus may have been around earlier than previously thought.