The sharp rise in cases and the geographical spread of the coronavirus outside China confirm WHO fears over dealing with the crisis, experts warned Sunday as they appealed for ever greater vigilance.
"There has been a profound shift in the direction that COVID-19 (new coronavirus) is taking over the past 48 hours," said Professor Devi Sridhar, Director of the Global Health Governance Programme at the University of Edinburgh Medical School.
"The WHO and its member state governments now need to be thinking about transitioning from containment to mitigation, ie. reducing the negative impacts of continued transmission," Sridhar warned.
On Friday, World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus had already sounded the alarm, saying the window to stem the virus was shrinking.
"We are still in a phase where containment is possible... our window of opportunity is narrowing," he warned, adding if countries did not quickly mobilise to counter the virus spread, matters could get "messy."
He also warned that Africa's poor health infrastructure left it vulnerable to the COVID-19 disease, which has spilled out of China to more than 25 countries.
Those fears have been compounded by three fatalities in recent days in Italy -- where some 50,000 people are in lockdown -- eight in Iran and six in South Korea.
The WHO has expressed concern at the apparent emergence of cases without a clear epidemiological link to China, where it emerged.
"It's what we call the passage to community transmission," said Professor Arnaud Fontanet, specialist in epidemiology of emerging diseases at France's Pasteur Institute.