Italy, South Korea and Iran reported sharp rises in coronavirus infections on Monday, but China relaxed curbs on movement as the rate of new infections there eased and a visiting World Health Organisation team reported steep declines in visits to clinics.

South Korea reported 231 new cases, taking its total to 833. Many are in its fourth-largest city, Daegu, which became more isolated with Asiana Airlines and Korean Air suspending flights there until next month.

Iran, which announced its first two cases last Wednesday, said it now had 61 cases and 12 deaths. Most of the infections were in the Shia holy city of Qom.

Elsewhere in West Asia, Bahrain and Iraq reported their first cases and Kuwait reported three cases involving people who had been in Iran.

Saudi Arabia, Kuwait, Iraq, Turkey, Pakistan and Afghanistan imposed restrictions on travel and immigration from Iran. Afghanistan also reported its first case, officials said.

Europe’s biggest outbreak is in Italy, with some 150 infections — compared with just three before Friday — and a sixth death.

In northern Italy, authorities sealed off the worst-affected towns and banned public gatherings across a wide area, halting the carnival in Venice, where there were two cases.

Austria briefly suspended train services over the Alps from Italy after two travellers coming from Italy showed symptoms of fever.

Both tested negative for the new coronavirus but Austrian interior minister Karl Nehammer said a task force would meet on Monday to discuss whether to introduce border controls.

The virus has put Chinese cities into lockdown in recent weeks, disrupted air traffic to the workshop of the world and blocked global supply chains for everything from cars and car parts to smartphones.

But China’s actions, especially in the city of Wuhan, the centre of the outbreak, had probably prevented hundreds of thousands of cases, the head of the WHO delegation in China, Bruce Aylward, said, urging the rest of the world to learn the lesson of acting fast.

“The world is in your debt,” Aylward said in Beijing, addressing the people of Wuhan. “The people of that city have gone through an extraordinary period and they’re still going through it.”

The surge of cases outside mainland China triggered sharp falls in global share markets and Wall Street stock futures as investors fled to safe havens. European share markets suffered their biggest slump since mid-2016, gold soared to a seven-year high, oil tumbled nearly 4 per cent and the Korean won fell to its lowest level since August.

But US treasury secretary Steven Mnuchin cautioned against jumping to conclusions about the impact on the global economy or supply chains, saying it was simply too soon to know.

The WHO’s Aylward said multiple data sources backed the trend of declining cases but an official with China’s National Health Commission, Liang Wannian, said more than 3,000 medical staff had become infected, most of them in Hubei, and likely because of the lack of protective gear and fatigue.

Excluding Hubei, mainland China reported 11 new cases.