The coronavirus was circulating in Europe and China months before officials identified the outbreak in Wuhan, studies show

The coronavirus was circulating in Europe and China months before officials identified the outbreak in Wuhan, studies show

December 31 marks the anniversary of the first confirmed coronavirus cases in Wuhan.

But a growing body of evidence suggest the virus was circulating in China and some European countries months before that.

In the US, meanwhile, a study found that some people had coronavirus antibodies in December 2019.

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Almost exactly one year has passed since the World Health Organization announced the first confirmed cases of the new coronavirus.

Yet the virus' origin and the true timeline of its worldwide spread remain a mystery. A growing body of evidence now suggests it was circulating months before the first cases captured global attention in Wuhan, China.

A study from Milan's National Cancer Institute found that four of Italy's coronavirus cases dated back to October 2019. Research from China shows people were getting sick in Wuhan in November and early December: One analysis, based on satellite images of Wuhan hospitals and online searches for COVID-19 symptoms in the area, suggested the virus may have started circulating there as early as late summer.

Although pinpointing the exact date of the virus's first jump from animals to people is impossible without more data, many studies suggest the pandemic's December anniversary is arbitrary.

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