New evidence suggests coronavirus was likely spreading in the US and France as early as December

Morgan McFall-Johnsen 21 hours ago

New evidence from Florida and France suggests that the coronavirus had already spread out of Wuhan, China, and begun traveling across the globe as early as December.

The findings come as researchers test samples from patients with respiratory illnesses who went to hospitals in December, January, and February. The results suggest the virus could have begun spreading through communities outside China weeks earlier than previously realized.

“It’s really important that we look further into this,” Maria Van Kerkhove, the World Health Organization’s COVID-19 technical lead, said in a press briefing on Wednesday. “Some countries may look backwards and may look at some of those samples that were stored in January or in December and may retest those. So it’s possible that we may see some of those samples testing positive for COVID-19.”

A new genetic analysis lends further credence to an earlier timeline of spread. The study, from scientists at University College London’s Genetics Institute, found that most of the virus’s genetic mutations (which so far don’t have known effects on symptoms or contagiousness) exist in all the hardest-hit countries. This suggests worldwide spread likely began “from extremely early on in the pandemic,” the researchers wrote. Their work was published Tuesday in the journal Infection, Genetics and Evolution.