Several European countries have announced their first Covid-19 coronavirus cases, with all appearing to be linked to the growing outbreak in Italy.
Austria, Croatia and Switzerland - as well as Algeria in Africa - all said the cases involved people who had been to Italy.
The first positive virus test in Latin America has also been recorded in a Brazilian resident just returned from Italy.
Italy has in recent days become Europe's worst-affected country, with more than 300 cases and 11 deaths.
Its neighbours have decided closing borders would be "disproportionate". Health ministers from France, Germany, Italy and the EU Commission committed to keeping borders open at a meeting on Tuesday as new cases of the virus emerged throughout Europe and in central and southern Italy.
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"We're talking about a virus that doesn't respect borders," Italian Health Minister Roberto Speranza said.
His German counterpart Jens Spahn said the neighbours were taking the situation "very, very seriously" but acknowledged "it could get worse before it gets better".
In the UK, schoolchildren returning from holidays in northern Italy were being sent home, with the government issuing new guidance to travellers.
UK Health Secretary Matt Hancock however said there were no plans to stop flights from Italy, which attracted about three million British visitors each year.
"If you look at Italy, they stopped all flights from China and they're now the worst-affected country in Europe," he said.
The latest around Europe:
- In Austria, a young Italian couple who live in Innsbruck in the Tyrol were confirmed to have the virus. One of the pair worked at a hotel, which was put in lockdown. The couple's home was also sealed off
- Switzerland said a man in his 70s living in Ticino, bordering Italy, had been infected in the city of Milan on 15 February and was now in isolation
- A man in Croatia who recently returned from Italy became the first confirmed patient in the Balkans
- In Spain's Tenerife, up to 1000 guests were locked down in a hotel after an Italian doctor and his wife tested positive for the virus
- Spain reported its first case on the mainland, involving a woman in Barcelona who had been to northern Italy
- France and Germany also reported new cases involving people who had recently been to northern Italy
What's the global picture?
Italy is one of three global hotspots outside China.
In Iran, fewer than 100 people have officially been infected but deaths have reached 16 - the second-highest number after China - and it's assumed the true number of infections are far higher.
The infection of the country's deputy health minister has deepened fears that the virus has already spread widely.
More than 1000 people have been infected in South Korea, where 12 people have died. The country has the most infections outside China.
Many of the cases are linked to a branch of the Shincheonji Church of Jesus in the city of Daegu. All the church's more than 215,000 members were being tested by health authorities, according to reports.
In Brazil, local media reported on Tuesday that an initial test on a 61-year-old man who had recently been to northern Italy had come out positive.
They said the man from São Paulo would be tested again for final confirmation.
The individual, whose name was not given, arrived back in Brazil at the height of the carnival festivities, when millions of people travel around the country. Officials feared the timing of his return made it more likely the coronavirus could have spread.
Most of the cases of the Covid-19 coronavirus remain in China, where the virus originated last year.
According to the latest figures published on Wednesday, 78,064 people had been infected in China since the outbreak began, while global infections reached 81,002.
Health officials also reported 52 more deaths in China on Tuesday, the lowest daily total in more than three weeks. The overall death toll in mainland China reached 2715.
Numbers of new infections have been declining in China, and attention has now turned to clusters of cases abroad and transmission between countries.
The director general of the World Health Organization (WHO) said the sudden increase in cases in countries outside China was "deeply concerning".
On Tuesday, the US Centers for Disease Control and Prevention warned the virus could bring "severe" disruption to the US, with one official saying it was not a question of if, but when the virus would become a global pandemic.
Meanwhile, US Secretary of State Mike Pompeo urged all nations to "tell the truth about the coronavirus", saying that Washington was concerned that Iran may have concealed "vital details" about its outbreak.
Of the current hot-spots outside China, Iran is the most concerning because of the lack of an accurate picture of how widespread the outbreak really is, said Dr Nathalie MacDermott, an expert in infectious diseases at King's College London.
Most of the reported cases have been people who are elderly and dying, she said. "It seems like we're hearing about the tip of the iceberg and missing that chunk underneath who may be younger and may not be particularly unwell."
There are fears that the many Muslim Shia pilgrims and migrant workers who will have travelled between Iran and other parts of the region in recent weeks could have already spread the virus.
Iran is believed to have been the source of the first cases reported by neighbouring Afghanistan, Bahrain, Iraq, Kuwait and Oman, which have now imposed restrictions on travel to and from the Islamic Republic.