Thousands of Covid-like cases raise risk of future pandemics
New survey finds coronaviruses from animals may cause 400,000 infections a year
Hundreds of thousands of people may be infected annually by animals carrying coronaviruses related to the one that causes Covid-19 in China and Southeast Asia, according to a study emphasising the ongoing pandemic threat from spillover events.
An average of 400,000 such infections occur annually, most going unrecognised 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 on Thursday, before peer review and publication. Still, each spillover represents an opportunity for viral adaptation that could lead to a Covid-like outbreak.
The question of where and how the virus that causes Covid-19 emerged has become particularly contentious, with some leaders blaming a hypothetical leak from a lab in Wuhan, China, that studies the pathogens. The new research, supported by the US National Institute of Allergy and Infectious Diseases, builds on evidence that bats are the main host animals for viruses such as Sars-CoV-2 and that people living near their roosts are especially vulnerable. ..