The World Health Organisation (WHO) has declared an international emergency over the deadly coronavirus that originated in China.
WHO director-general Tedros Adhanom Ghebreyesus announced the decision after a marathon meeting of its emergency committee, an independent panel of experts, amid mounting evidence of the virus' spread to some 18 countries.
"The main reason for this declaration is not because of what is happening in China, but because of what is happening in other countries," Dr Ghebreyesus told reporters on Thursday.
"Our greatest concern is the potential for the virus to spread to countries with weaker health systems, and which are ill-prepared to deal with it."
The declaration is a rarely used designation that could lead to improved international co-ordination in tackling the disease.
"This is not a vote of no confidence in China," he said, emphasising repeatedly that the measure was intended to help other countries less able to cope and praising the Chinese government for taking swift action to tackle the outbreak.
Tedros Adhanom Ghebreyesus, Director General of the World Health Organisation says there is no reason to restrict travel to China. Source: AAP
"We must all act together now to limit further spread.... We can only stop it together," said Tedros, who travelled to China this week and met with President Xi Jinping.
Tedros also said there was "no reason" for any of the international travel or trade restrictions announced in recent days, such as flight suspensions, border closures and quarantine for apparently healthy travellers.
Top airlines including Air France, British Airways and Lufthansa have suspended or cut back services to China.
The WHO's Emergency Committee, an advisory body of international experts, said in a statement that evidence had shown that restricting movement of people and goods during public health emergencies "may be ineffective and may divert resources from other interventions".
"Further, restrictions may interrupt needed aid and technical support, may disrupt businesses, and may have negative effects on the economies of countries affected by the emergencies," the committee said.
But it added that "in certain specific circumstances, measures that restrict the movement of people may prove temporarily useful" - a possible reference to lockdowns within China that have affected millions of people.
WHO stopped short of declaring an emergency last week because its emergency committee was divided over the issue.
More than 7,700 people have been infected with the virus - almost all of them in China - and 170 have died.
A doctor at a community health station checks the body temperature of a visitor in Hangzhou in east China's Zhejiang province Source: Getty Images
The WHO said there have also been 82 confirmed cases in 18 other countries, including cases of onward transmission in Germany, Japan, the United States and Vietnam.
There are nine confirmed cases in Australia.
The WHO has called a public health emergency of international concern only five times since the relevant legislation took effect in 2007 - for swine flu, polio, Zika and twice for Ebola outbreaks in Africa.
The designation, which is reviewed every three months, allows the WHO to issue global recommendations that the international community is expected to follow.
Governments, companies and people around the world have already been escalating efforts to contain the illness, which is believed to have emerged from an animal market in the central Chinese city of Wuhan.
Many countries have urged their citizens not to visit China, while some have banned entry for travellers from Wuhan and Russia said it was closing its far eastern border with China over the outbreak.
