The coronavirus has now been detected on every continent on Earth except Antarctica, leading to new fears in China about how to keep the virus out.
With Brazil confirming Latin America's first case, the potentially deadly disease has now reached every corner of the globe after emerging in Wuhan in late 2019.
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As officials around the world battle to contain the disease that experts believe can spread without showing symptoms, China is now facing a fresh challenge – keeping it out.
This week the number of new cases of the virus outside China exceeded those inside the country for the first time.
Now, news that the infection had been carried into the country by a traveller from Iran raised the ire of users on social media. Many fumed the drastic lockdown measures the country had taken may have been in vain.
China's local authorities said a case of "imported coronavirus" had been found in the Ningxia region, after a 23-year old translator returned from Iran where he worked.
A detailed report in state media said the man, known as Ding, travelled via Moscow, used a ride sharing app and took an overnight train.
A hashtag about the Ningxia case ratcheted up 100 million views on China's Weibo platform.
"So many domestic efforts can't be wasted because of the overseas arrival!" one online user wrote in a comment echoed by many others.
One user pointed out that the patient came back into China along the route of the Belt and Road Initiative — President Xi Jinping's signature global infrastructure project.
China is now facing the ironic possibility of adopting "targeted prevention and control measures" for those coming into the country. People landing in the Chinese capital from countries hit by the epidemic will have to self-quarantine.
It comes after other countries around the world banned flights from China in a bid to stop the virus getting out.
On Thursday, the World Health Organisation (WHO) warned the virus is at a "decisive point" that could "get out of control" if countries did not act to contain it.
"We're at a decisive point," WHO chief Tedros Adhanom Ghebreyesus told reporters in Geneva.
"It's what's happening in the rest of the world that's now our greatest concern," he said.
Tedros told affected countries: "If you act aggressively now, you can contain this virus, you can prevent people getting sick, you can save lives."
The new virus has infected more than 82,000 people and killed 2800 worldwide since it originated in late December in China's Hubei province
Northern Italy, South Korea, Japan and Iran have been particularly hard hit. Eleven towns in Italy have been locked down while authorities work to track the source of the disease. It has also spread throughout Europe's open border network, including to Croatia, France, Germany, Austria, Switzerland and Greece.
"Viruses don't know borders and they don't stop at them," said Roberto Speranza, the Italian health minister, as towns in the country's north remained under armed guard and supermarket shelves were bare.