Boris Johnson has declared the coronavirus outbreak the “worst health crisis in a generation” but has stopped short of forcing drastic closures to contain the spread.

The UK prime minister announced basic measures such as staying at home for seven days with a new cough or higher temperature, advising over-70s not to go on cruises and discouraging international school trips.

He said the government was “considering” banning major events and sporting but schools would remain open.

It comes as China urged nations to mobilise and take dramatic steps to fight the pandemic which its senior medical officer said could be over by June if it was tackled with extreme policies.

The source of the world pandemic, the Chinese province of Hubei, recorded single digit new infections for the first time, with China claiming the country’s infection peak had passed.

Chinese authorities credit strict measures they have taken, including placing Hubei under near total lockdown, with preventing big outbreaks in other cities, and say other countries should learn from their efforts.

“Broadly speaking, the peak of the epidemic has passed for China,” National Health Commission spokesman Mi Feng said.

“The increase of new cases is falling,” Zhong Nanshan, the Chinese government’s senior medical adviser said, as long as countries take the outbreak seriously and are prepared to take firm measures, it could be over worldwide in a matter of months.

“My advice is calling for all countries to follow WHO instructions and intervene on a national scale,” he said. “If all countries could get mobilised, it could be over by June.”

Around the world, countries have announced increasing restrictions on mass gatherings as the WHO finally declared a pandemic amid concerns many nations were not taking the virus emergency seriously.

There are reports the Australian Grand Prix could be cancelled after the withdrawal of the McLaren racing team after a member tested positive for the virus.

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Ireland will close all schools and cultural centres from Friday until March 29 after recording its first death and 43 infections while France will close all creches, schools and universities from next week.

“Our advice is that all indoor gatherings of more than 100 people and all outdoor gatherings of more than 500 people should be cancelled,” Irish Prime Minister Leo Varadkar said.

Rome’s 900 Catholic churches have been ordered closed because of the coronavirus pandemic in a move believed to be unprecedented in modern times.

The cruise liner company Princess Cruises will halt its 16 ships for two months after recent disastrous outbreaks  – notably the Diamond Princess – which resulted in hundreds of infections and many deaths.

However Europe reacted angrily to US president Donald Trump’s shock decision to ban all travel to 26 EU countries (excluding the UK and Ireland).

In a joint statement by EU Council president Charles Michel and the European Commission President Ursula von der Leyen, the two leaders insisted the coronavirus pandemic was a “global crisis, not limited to any continent and it requires co-operation rather than unilateral action”.

“The European Union disapproves of the fact that the US decision to improve a travel ban was taken unilaterally and without consultation,” they said on Thursday.

The coronavirus pandemic continues to take its toll on events and operations too with a Russian-European mission to send a rover to Mars postponed by two.

The European Space Agency and Russia’s Roscosmos say they are postponing a planned joint mission to Mars until 2022, in part due to travel restrictions resulting from the coronavirus outbreak.

Canadian PM virus scare

Canadian Prime Minister Justin Trudeau and his wife Sophie are in self-isolation after she came down with flu-like symptoms and was tested for coronavirus, according to an official statement.

The 48-year-old Liberal leader is exhibiting no symptoms and will continue to work from home until the results of his wife’s test comes in, the statement said.

However, face-to-face meetings with provincial premiers scheduled for Thursday and Friday will instead be held by phone.

Canadian PM Justin Trudeau is in self-isolation after his wife came down with symptoms.

“Having recently returned from a speaking engagement in London, UK, the Prime Minister’s wife Sophie Gregoire Trudeau began exhibiting mild flu-like symptoms including a low fever late last night,” the statement from the prime minister’s office read.

“She immediately sought medical advice, and is being tested for the COVID-19 virus. She is self-isolating at home awaiting test results, and her symptoms have since subsided.”

The statement does not mention whether their three children are staying home as well.

China’s slow recovery

With the marked slowdown of the spread of the virus in China, more businesses have reopened, with authorities cautiously easing strict containment measures.

Hubei province announced on Thursday a further loosening of travel restrictions and will also allow some industries to resume production in two of its cities and two counties.

Hubei’s economy, driven by manufacturing and trade, including a sizeable auto sector in the provincial capital Wuhan, had been virtually shuttered since January 23.

While the virus is spreading quickly globally, its progress in China has slowed markedly in the past seven days.

In all, 15 new cases were recorded in mainland China on Wednesday, down from 24 the day before. Seven of the new cases were outside Hubei, including six imported from abroad.

While only 85 of the cases in China have come from abroad, the rising number of such incidences has prompted authorities to shift their focus on containing the risk of imported cases.

The total number of cases recorded in mainland China was 80,793. As of Tuesday, 62,793 people had recovered and been discharged from hospital, or nearly 80 pert cent of the infections.

As of the end of Wednesday, the death toll in mainland China had reached 3,169, up by 11 from the previous day. Hubei accounted for 10 of the new deaths, including seven in Wuhan.

–with AAP