Deaths from China’s new virus rose to 17 on Wednesday with more than 540 cases confirmed, increasing fears of contagion from an infection suspected to originate from illegally-traded wildlife.

The previously unknown, flu-like coronavirus strain is believed to have emerged from an animal market in central Wuhan city, with cases now detected as far away as the US.

Contrasting with its secrecy over the 2002-03 Severe Acute Respiratory Syndrome (SARS) that killed nearly 800 people, China’s communist government has this time given regular updates to try to avoid panic as millions travel for the Lunar New Year.

“The rise in the mobility of the public has objectively increased the risk of the epidemic spreading,” National Health Commission vice-minister Li Bin said.

The World Health Organisation (WHO) was meeting to rule if the outbreak was a global health emergency.

After official appeals to stay calm, many Chinese were cancelling trips, buying face masks, avoiding public places such as cinemas and shopping centres, and even turning to an online plague simulation game or watching The Flu as a way to cope.

“The best way to conquer fear is to confront fear,” said one commentator on China’s Twitter-like Weibo.

The virus has spread from Wuhan around China to population centres including Beijing, Shanghai, Macau and Hong Kong.

The latest death toll in Hubei province, of which Wuhan is the capital, rose from nine to 17 by midday on Wednesday, state television quoted the provincial government as saying.

The China Daily said 544 cases had now been confirmed in the country. Abroad, Thailand has confirmed four cases, while the US, Taiwan, South Korea and Japan have each reported one.

President Donald Trump said the US’s Centres for Disease Control and Prevention had a good containment plan. “We think it is going to be handled very well,” he said at Davos in Switzerland.

Airports round the world stepped up screening from China. Russia said it had strengthened its sanitary and quarantine control, Britain said it would start enhanced monitoring of passengers from Wuhan, and Singapore started screening all passengers from China.

The Chinese-ruled gambling hub of Macau confirmed its first case of pneumonia linked to the coronavirus and tightened body-temperature screening measures.

A first case emerged in Hong Kong on Wednesday, media reported, with the patient arriving via railway from the mainland. “The whole world is watching,” the city’s commerce secretary, Edward Yau, said.