A shift in the crisis appeared to be taking shape: Hundreds of patients were released from hospitals at the epicentre of the outbreak in China, while the World Health Organization reported that nine times as many new infections were recorded outside the country as inside it over the past 24 hours.

Alarming clusters of disease continued to swell in South Korea, Italy and Iran, and the virus turned up for the first time in New York, Moscow and Berlin, as well as Latvia, Malaysia, Morocco, Tunisia, Senegal, Jordan and Portugal. The worldwide death toll topped 3,000 and the number of those infected rose to about 89,000 in 70 countries on every continent but Antarctica.

Global health officials sought to reassure the public that the virus remains a manageable threat.

"Containment is feasible and must remain the top priority for all countries," WHO chief Tedros Adhanom Ghebreyesus said.

Around the world, the crisis reshaped the daily routines of millions of people.

Across Japan, children stayed home after the government announced the closing of schools until April. In Paris, the galleries of the Louvre museum were off limits. With Israel holding a national election, special voting booths were set up for those under quarantine. In Germany, Chancellor Angela Merkel was rebuffed by her interior minister when she extended her hand to greet him.

At the United Nations, officials said they were postponing a major conference on women that had been expected to bring up to 12,000 people from its 193 member countries to New York next week.

The Organization for Economic Cooperation and Development warned that the world economy could contract this quarter for the first time since the international financial crisis more than a decade ago.

"Global economic prospects remain subdued and very uncertain," the agency said.

Nevertheless, the Dow Jones Industrial Average soared nearly 1,300 points as stocks roared back from a seven-day rout on hopes that central banks will take action to shield the global economy from the effects of the outbreak.

Over 100 cases have been confirmed in the US, more almost certain in the coming weeks. Thousands of test kits were on their way to state and local labs, and new guidelines intended to expand screening were put in place.

"In this situation, the facts defeat fear. Because the reality is reassuring. It is deep-breath time," New York Governor Andrew Cuomo said.

The message was echoed by global health officials, who said they were encouraged that even in some countries that had taken far less aggressive measures than China's, the virus remains largely in check.

Because the virus is not transmitted as easily as the flu, "it offers us a glimmer ... that this virus can be suppressed and contained," said Dr Mike Ryan, the WHO's emergencies chief.

China reported just 202 new cases, its lowest daily count since January 21, and the city at the heart of the crisis, Wuhan, said 2,570 patients were released. At the largest of 16 temporary hospitals that were rapidly built in Wuhan in response to the outbreak, worries over the availability of supplies and protective gear eased, along with the pressure on the medical staff.

Dr Zhang Junjian, who leads a temporary hospital in Wuhan with a staff of 1,260, said optimism is high that the facility will no longer be needed in the coming weeks.

Australian Associated Press