The novel coronavirus has likely been circulating in humans since late last year, a new genetic analysis by British researchers shows, according to CNN.
The researchers examined the virus taken from more than 7,600 patients worldwide. They studied viral sequences, examining samples taken at different times and from different places.
Researchers published their findings in the journal Infection, Genetics and Evolution.
Their analysis indicates the virus first started infecting people at the end of 2019. The analysis also suggests the virus was infecting people in Europe, the U.S. and in other countries before the first official cases were reported in January and February.
"All these ideas about trying to find a Patient Zero are pointless because there are so many patient zeros," Francois Balloux, PhD, a genetics researcher at the University College London Genetics Institute and study author, told CNN.
There is now mounting evidence that the virus may have been spreading outside of China since last year. French physicians identified what could be the earliest known European COVID-19 case, which occurred in December.
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