The news has fuelled anxiety about the prospect of coronavirus spreading more easily across borders – just as millions begin travelling for lunar new year celebrations.
Confirming two cases of the infection in China’s Guangdong province having been caused by human-to-human transmission, Zhong Nanshan, a respiratory expert, warned over the potential for the virus to garner strength as it passes from east to west.
Over the weekend, the number of people infected with the virus tripled, with some 139 new cases.
It brought the total number of people infected to 440 cases.
Most of those infected are isolated to the province of Wuhan, though the respiratory illness has also been detected in Beijing, Shanghai and Shenzhen.
The new strain of coronavirus causes a type of pneumonia.
The virus is thought to have originated from a market.
Though, officials and scientists are yet to determine exactly how it has been spreading so quickly.
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Patients may also have difficulties in breathing.
When the virus was first contracted by humans from a seafood market in Wuhan, experts believed it could not be easily spread from human to human.
All coronaviruses are zoonotic, meaning they can be transferred between people and animals.
In 1918 the Spanish flu pandemic infected about 500 million people globally, which was a third of the world’s population.
However, a sharp rise in the disease since its initial discovery in December has proved the doctors wrong.
China has sold out of face masks and officials at airports are trying to control the outbreak.
The masks were being sold for ten times their original price.