LONDON : A group of leading UK and US scientists, including Indian-origin Cambridge University immunology and infectious disease expert Ravindra Gupta, on Friday called for more investigation to determine the origin of the COVID-19 pandemic, including the theory of an accidental release from a lab in the central Chinese city of Wuhan.In a letter published in the journal ‘Science’, the experts from world leading universities such as Harvard, Stanford and MIT said knowing how COVID-19 emerged is critical for informing global strategies to mitigate the risk of future outbreaks.They caution that hypotheses about both natural and laboratory spillovers must be taken seriously until there is sufficient data.“Theories of accidental release from a.