Coronaviruses jump from animals to humans 400,000 times annually, study claims

Hundreds of thousands of people may be infected annually each year in China and Southeast Asia by animals carrying coronaviruses related to the one that causes COVID-19, according to a study emphasizing the ongoing pandemic threat from spillover events.

An average of 400,000 such infections occur annually, most going unrecognized because they cause mild or no symptoms and aren’t easily transmitted between people, researchers with the EcoHealth Alliance and Singapore’s Duke-NUS Medical School said in a study released Thursday before peer review and publication. Still, each spillover represents an opportunity for viral adaptation that could lead to a an outbreak similar to that seen with COVID-19.

The question of where and how the virus that causes the disease emerged has become particularly contentious, with some leaders blaming a hypothetical leak from a lab in Wuhan, China, that studies the pathogens.