British researchers have published a new map predicting the global spread of the novel coronavirus over the next three months.
The graphic is based on the mobile phone and flight data of 60,000 of an estimated five million Wuhan residents who fled during the critical two weeks before the outbreak city was placed under lockdown.
The theoretical study, by researchers from Southampton University's World Pop Project research group, used map location data from Chinese tech giant Baidu and international flight itineraries to make a predictive global risk map for the likely spread of the virus from Wuhan, reports news.com.au.
It revealed an estimated 59,912 air passengers — including 834 infected with 2019-nCoV — flew from Wuhan to no less than 382 cities outside of mainland China in the days leading up to January 23, when the city was placed in quarantine.
"The majority of these cities were in Asia, but major hubs in Europe, the US and Australia were also prominent, with strong correlation seen between predicted importation risks and reported cases seen," the authors wrote.
"Because significant spread has already occurred, a large number of airline travellers (3.3 million under the scenario of 75 per cent travel reduction from normal volumes) may be required to be screened at origin high-risk cities in China and destinations across the globe for the following three months of February to April, 2020 to effectively limit spread beyond its current extent."
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The top 10 global destinations for travellers from high-risk Chinese cities around Lunar New Year were Thailand, Japan, Hong Kong, Taiwan, South Korea, the United States, Malaysia, Singapore, Vietnam and Australia.
Within Africa, Egypt, South Africa, Ethiopia, Mauritius, Morocco, Nigeria and Kenya topped the list.
"Further spread of 2019-nCoV within China and international exportation is likely to occur," the authors concluded.
"All countries, especially vulnerable regions, should be prepared for efforts to contain the 2019-nCoV infection."
The researchers noted a statistic confirmed by Wuhan authorities: five million of the city's 11 million population had already left by the time it was placed into lockdown just two days before Lunar New Year Day.
"Where these travellers went and how high the risk of further spread of the virus within and beyond China remains an open question," they wrote.
"It's definitely too late," Jin Dong-Yan, a molecular virologist at Hong Kong University's School of Biomedical Sciences, told AP.
"Five million out. That's a big challenge. Many of them may not come back to Wuhan but hang around somewhere else.
"To control this outbreak, we have to deal with this. On one hand, we need to identify them. On the other hand, we need to address the issue of stigma and discrimination."
Last week, multiple countries, including Australia and the US, banned non-Australian visitors from China and warned citizens against travelling to the mainland.
The latest figures show the virus continues to spread, with more than 40,500 cases confirmed worldwide, 40,146 of them on mainland China.
The death toll rose to 910 while another 6000 remain in a "severe" condition in hospital.
All but two deaths have occurred on mainland China, with Hong Kong and the Philippines recording one each.
Philippines recording one each.
The biggest single cluster of infections outside China is aboard cruise ship Diamond Princess, which remains quarantined off Japan after 135 people, including four Australians, tested positive for the virus. There are around 3700 passengers and crew on the ship.
"Our guests and crew on board Diamond Princess are the focus of our entire global organisation right now and all of our hearts are with each of them," Princess Cruises president Jan Swartz said in a statement.
"In this unprecedented situation, the Japanese Ministry of Health authorities are working with us collaboratively on additional enhancements, approving new procedures as we adapt our process to the unique challenges of this situation."
Like its cousins SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome), 2019-nCoV — also known as novel coronavirus — is a zoonotic commonly found in bats which mutated to enable human to human transmission.
The latest strain is believed to have originated from Wuhan's Huanan Seafood Wholesale Market, where a perfect storm of domestic and exotic animals — both live and dead — kept in cramped, unhygienic conditions, facilitated the species jump.
In the case of both SARS and MERS, the virus was transmitted from bats to humans via an intermediate reservoir, or host. With SARS it was palm civets, with MERS it was camels.
The intermediate remains unknown for 2019-nCoV but suspects include the pangolin — the world's most trafficked animal — and the snake, although direct bat to human transmission has not been ruled out.