Coronavirus was in the UK weeks before the first acknowledged cases, according to fresh analysis on the outbreak. And there were multiple 'patient zeros' which quickly spread the virus scientists believe.
A new genetic analysis of coronavirus, which causes Covid-19, taken from more than 7,600 patients worldwide shows it has been circulating since late last year when it first emerged from Wuhan in China.
Researchers in the UK have been studying mutations in the virus and found evidence of how quickly it spread - but no evidence that it is becoming easier to spread or deadlier.
Francois Balloux of the University College London Genetics Institute told CNN it will be impossible to find the "first" patient in any country. Sign up to get the