The new study reports on 44,672 cases confirmed in China as of Feb. 11. The virus caused severe disease such as pneumonia in 14 per cent of them and critical illness in 5 per cent.

The U.N. health agency’s director-general, Tedros Adhanom Ghebreyesus, urged governments to step up their efforts to prepare for the virus, saying “it’s impossible to predict which direction this epidemic will take.”