He said while just 1 per cent of the more than 6,000 cases have been recorded to date outside of China, person-to-person transmission has been recorded in 3 countries outside of it.
This is potential for further global spread and that is why he has called for the Emergency Committee to reconvene.
Dr Tedros returned to Geneva from China, where he met President Xi Jinping and the Ministers of Health and Foreign Affairs, said the Spokesperson for the UN Secretary General in a regular briefing in New York on Wednesday.
It was agreed that WHO will send international experts to visit China as soon as possible to work with Chinese counterparts on increasing understanding of the outbreak and guide global response efforts.
For its part, UNICEF has sent respiratory masks and protective suits for health workers and that shipment has arrived in Shanghai.
The agency will be sending more items in the coming days and weeks.
UNICEF Executive Director Henrietta Fore said while they may not know enough about the virus’ impact on children or how many may be affected, they do know that close monitoring and prevention are key. "Time is not on our side," she added.