The US evacuated citizens from a coronavirus-infected cruise ship in Japan on Monday, with other nations preparing to follow suit as the deathtoll in the Chinese epicentre of the outbreak topped 1,700.

The virus has sickened more than 70,500 across China and prompted global efforts to contain an outbreak that has spread to nearly 30 countries, sparking panic buying and economic jitters.

With fresh cases emerging daily in Japan, the government has advised citizens to avoid mass gatherings, and on Monday cancelled celebrations for the Emperor’s birthday – an annual jamboree that sees thousands of well wishers descend on central Tokyo.

Beijing’s municipal authorities have ordered everyone arriving in the capital to self-quarantine for 14 days, the presumed incubation period of the virus.

Outside China, the biggest cluster of infections is on the Diamond Princess cruise ship off Japan’s Yokohama, where 355 cases have been diagnosed, despite passengers being confined to their cabins during a 14-day quarantine.

As criticism grows of Japan’s handling of the ship crisis, governments are scrambling to repatriate their citizens, with Canada, Australia, Italy, and Hong Kong poised to follow Washington’s lead.

Prime Minister Scott Morrison said the more than 200 Australians still on board would be evacuated on Wednesday.

He said they would be subject to another 14 days of quarantine at a former mining camp near Darwin, where 266 people previously evacuated from China are being held.

Early on Monday, a convoy of buses driven by people in head-to-toe protective suits removed US passengers from the ship after a makeshift passport control.

There were no health checks at that point, said US passenger Sarah Arana, a 52-year-old medical social worker, who said the US government should have acted “much sooner, at the beginning”.

“I am happy and ready to go. We need a proper quarantine. This was not it,” Arana said before leaving the ship.

The US embassy in Japan said two jets had left Japan en route to the US. Those on board were expected to undergo a further 14-day quarantine period on US soil.

Some US passengers on the ship, however, declined the government’s offer.

“My health is fine. And my two-week quarantine is almost over. Why would I want to be put on a bus and a plane with other people they think may be infected when I have spent nearly two weeks isolated from those people?” tweeted Matt Smith.

Forty US passengers tested positive for the virus and were taken to hospitals in Japan, said Anthony Fauci, a senior official at the National Institutes for Health. It was not immediately clear if they were already counted among the 355 known cases on the ship.

In China, authorities have placed about 56 million people in Hubei under quarantine, virtually sealing off the province from the rest of the country in an unprecedented effort to contain the virus.

New cases outside the epicentre have been declining for the last 13 days. There were 115 fresh cases outside the central province announced on Monday – sharply down from nearly 450 a week ago.

Chinese authorities have pointed to the slowing rise in cases as proof their measures are working, even as the death toll climbed to 1,770.

But World Health Organisation head Tedros Ghebreyesus has warned it is “impossible to predict which direction this epidemic will take”.

And concerns remain about global transmission, especially on cruise ships, which appear to have become especially virulent breeding grounds.