President Biden has asked his intelligence agencies to step up their efforts to get to the truth about the origins of COVID-19 amid growing concern that it emerged from a Chinese laboratory.
A string of senior scientists have recently admitted they may have leapt to conclusions in assuming the virus jumped from an animal host in the wild to humans.
And at the weekend fresh details emerged about how staff at the Wuhan Institute of Virology sought hospital treatment for COVID-like symptoms in November 2019.
