29/03/2020
- Virus may have jumped from animal to humans long before the first detection in Wuhan, according to research by an international team of scientists
- Findings significantly reduce the possibility of the virus having a laboratory origin, director of the US National Institute of Health says
An international team of scientists say the coronavirus may have jumped from animal to humans long before the first detection in China. Photo: AP
The
coronavirus that causes Covid-19 might have been quietly spreading among humans for years or even decades before the sudden outbreak that sparked a global health crisis, according to an investigation by some of the world’s top virus hunters.
Researchers from the United States, Britain and Australia looked at piles of data released by scientists around the world for clues about the virus’ evolutionary past, and found it might have made the jump from animal to humans long before the first detection in the central China city of Wuhan.
Though there could be other possibilities, the scientists said the coronavirus carried a unique mutation that was not found in suspected animal hosts, but was likely to occur during repeated, small-cluster infections in humans.
The study, conducted by Kristian Andersen from the Scripps Research Institute in California, Andrew Rambaut from the University of Edinburgh in Scotland, Ian Lipkin from Columbia University in New York, Edward Holmes from the University of Sydney, and Robert Garry from Tulane University in New Orleans, was published in the scientific journal Nature Medicine on March 17.
Dr Francis Collins, director of the US National Institute of Health, who was not involved in the research, said the study suggested a possible scenario in which the coronavirus crossed from animals into humans before it became capable of causing disease in people.
“Then, as a result of gradual evolutionary changes over years or perhaps decades, the virus eventually gained the ability to spread from human to human and cause serious, often life-threatening disease,” he said in an article published on the institute’s website on Thursday.
In December, doctors in Wuhan began noticing a surge in the number of people suffering from a mysterious pneumonia. Tests for flu and other pathogens returned negative. An unknown strain was isolated, and a team from the Wuhan Institute of Virology led by Shi Zhengli traced its origin to a bat virus found in a mountain cave close to the China-Myanmar border.
The two viruses shared more than 96 per cent of their genes, but the bat virus could not infect humans. It lacked a spike protein to bind with receptors in human cells.
Coronaviruses with a similar spike protein were later discovered in Malayan
pangolins
by separate teams from Guangzhou and Hong Kong, which led some researchers to believe that a recombination of genomes had occurred between the bat and pangolin viruses.
Doctors in Wuhan began noticing a surge in the number of people suffering from a mysterious pneumonia in December. Photo: Handout
But the new strain, or SARS-Cov-2, had a mutation in its genes known as a polybasic cleavage site that was unseen in any coronaviruses found in bats or pangolins, according to Andersen and his colleagues.
This mutation, according to separate studies by researchers from China, France and the US, could produce a unique structure in the virus’ spike protein to interact with furin, a widely distributed enzyme in the human body. That could then trigger a fusion of the viral envelope and human cell membrane when they came into contact with one another.
Some human viruses including HIV and Ebola have the same furin-like cleavage site, which makes them contagious.
It is possible that the mutation happened naturally to the virus on animal hosts. Sars (severe acute respiratory syndrome) and Mers (Middle East respiratory syndrome), for instance, were believed to have been direct descendants of species found in masked civets and camels, which had a 99 per cent genetic similarity.
There was, however, no such direct evidence for the novel coronavirus, according to the international team. The gap between human and animal types was too large, they said, so they proposed another alternative.
“It is possible that a progenitor of SARS-CoV-2 jumped into humans, acquiring the genomic features described above through adaptation during undetected human-to-human transmission,” they said in the paper.
“Once acquired, these adaptations would enable the pandemic to take off and produce a sufficiently large cluster of cases to trigger the surveillance system that detected it.”
They said also that the most powerful computer models based on current knowledge about the coronavirus could not generate such a strange but highly efficient spike protein structure to bind with host cells.
The study had significantly reduced, if not ruled out, the possibility of a laboratory origin, Collins said.
“In fact, any bioengineer trying to design a coronavirus that threatened human health probably would never have chosen this particular conformation for a spike protein,” he said.
The findings by Western scientists echoed the mainstream opinion among Chinese researchers.
Zhong Nanshan, who advises Beijing on outbreak containment policies, had said on numerous occasions that there was growing scientific evidence to suggest the origin of the virus might not have been in China.
“The occurrence of Covid-19 in Wuhan does not mean it originated in Wuhan,” he said last week.
A doctor working in a public hospital treating Covid-19 patients in Beijing said numerous cases of mysterious pneumonia outbreaks had been reported by health professionals in several countries last year.
Re-examining the records and samples of these patients could reveal more clues about the history of this worsening pandemic, said the doctor, who asked not to be named due to the political sensitivity of the issue.
“There will be a day when the whole thing comes to light.”
Source: SCMP
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20/02/2020
- A government task force has estimated a US$5 billion loss if Chinese students – angered and frustrated by the ban – cannot enrol for university
- The tourism sector is also likely to be hit by restrictions on travel from the mainland as Chinese visitors spend about U$8 billion in Australia each year
Some 150,000 Chinese nationals are enrolled at Australian universities, making up around 11 per cent of the student population. Photo: Shutterstock
Abbey Shi knows first hand the anger and frustration felt by Chinese students left stranded by the Australian government’s decision to ban travel from the mainland in response to the
coronavirus outbreak.
Shi, general secretary of the Students’ Representative Council at the University of Sydney, is in contact with more than 2,000 Chinese students who went home for the Lunar New Year holiday and now cannot return to
Australia with just weeks to go until the start of the new academic year.
“There is a lot of confusion about the ban and anger towards the government,” said Shi, an international student from Shanghai. Currently in Australia, she is sharing information with the stranded students via WeChat.
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“The
education sector in Australia is being commercialised and students are being treated like cash cows,” she said. “Universities don’t care about our affected career path, life, tenancy issues, our pets at home.”
Prime Minister Scott Morrison on Saturday announced that non-citizens – excluding permanent residents and their immediate family members – who arrived from or passed through mainland China within the previous 14 days would be denied entry to Australia as part of efforts to halt the spread of the coronavirus, which was first detected in December in the Chinese city of Wuhan.
Other countries including the
United States,
Singapore and the
Philippines have introduced similar travel restrictions in response to the outbreak, which has sickened more than 19,000 people in at least 26 countries and territories outside mainland China and claimed 425 lives.
The travel ban, which is due to be reviewed on February 15, has upended the plans of numerous Chinese students who were due to begin or return to their studies from late February following the summer break.
Tony Yan, a mathematics undergraduate at Australian National University (ANU), said he had been left out of pocket for several weeks’ rent after being stranded in his home province of Jiangsu, but hoped he could return before classes started on February 24.
“I think the Australian government should have given a few days earlier notice,” Yan said. “I haven’t paid the tuition yet, many others haven’t as well.”
About 150,000 Chinese nationals are enrolled at Australian universities, making up around 11 per cent of the student population – a far greater proportion than in Britain and the United States, which came in at 6 per cent and 2 per cent respectively, in a 2017 report from an Australian think tank.
Coronavirus: Australia evacuates 243 people from China as deaths mount
ANU Vice-Chancellor Brian Schmidt on Saturday described the travel ban as “disappointing”, pledging that the university would be “generous and flexible in supporting our students” through the coming weeks.
Monash University in Melbourne has delayed the start of its academic year, while other universities are exploring options such as online tuition and intensive summer courses.
Australian universities, some of which rely on Chinese students for nearly one-quarter of their revenue, are bracing to take a major financial hit due to the ban.
Phil Honeywood, the head of a government task force initially set up to manage the reputation of Australia’s international education sector in the wake of the country’s bush fires crisis, on Sunday warned the ban could cost universities A$8 billion (US$5.34 billion) if Chinese students could not enrol for the first semester of the year.
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Education minister Dan Tehan on Monday met with peak body Universities Australia to discuss ways to minimise fallout for the sector.
“Australia will remain an attractive study destination for Chinese students, but it may take several years for Chinese student numbers to recover,” said Salvatore Babones, associate professor at the University of Sydney and adjunct scholar at the Centre for Independent Studies. “Students who are already in the middle of a degree are likely to return at the first possible opportunity, even at the cost of missing one semester, but students who have not yet started may make other plans.”
But ANU tertiary education expert Andrew Norton said there remained too many unknowns, including the number of Chinese students stranded abroad, to gauge the impact of the ban.
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“This travel ban is a short-term policy to minimise the risk of disease spreading, which would be a more serious problem than a disruption to university timetables,” he said. “One of Australia’s major [education] competitors – the US – has a similar policy, and due to travel restrictions within China and the cancelling of commercial flights to and from China Australia’s competitors are unlikely to be able to take advantage.”
Norton noted that the sector had weathered previous outbreaks such as the 2003 outbreak of severe acute respiratory syndrome (Sars), and “although there were sometimes short-term dips in numbers, none of them have changed the long-term trend towards growth”.
The ban has also sent jitters throughout the tourism industry, which relies on Chinese visitors for a quarter of international spending. Nearly 1.5 million
visited Australia in 2018-19, Australian Bureau of Statistics records show, accounting for about one in eight arrivals.
Nearly 1.5 million Chinese nationals visited Australia in 2018-19, according to Australian Bureau of Statistics records. Photo: SCMP / Alkira Reinfrank
With Chinese tourists spending about A$12 billion (US$8 billion) in Australia each year, according to Tourism Research Australia, every month the travel ban remains in place could amount to billion-dollar losses for the sector.
Tourism Tropical North Queensland on Monday said the outbreak had already cost operators for Cairns and the Great Barrier Reef 25,000 direct bookings worth A$10 million. Chief executive Mark Olsen said the situation constituted a crisis for the industry that called for “unprecedented action” by the government.
David Beirman, senior lecturer in tourism at the University of Technology Sydney, said the ban was especially damaging for the industry as it came on the heels of devastating bush fires that had kept visitors away.
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“There is no doubt that the coronavirus outbreak following on so closely to the bush fires will combine to hit international tourism to Australia very hard,” Beirman said. “Later this month the Australian Bureau of Statistics will reveal the December 2019 tourism figures, which are expected to show at best a 25 per cent downturn in international visitor arrivals compared to December 2018. January 2020 is likely to be far worse as the impact of coronavirus will certainly be a factor.”
Others have raised concerns about the impact of the travel restrictions on public attitudes toward Chinese and Chinese-Australians, warning they could stoke latent prejudices.
“This is an overreaction from the Australian government, and in many ways it feels like it is a form of racial targeting,” said Erin Chew, national convenor of the Asian Australian Alliance. “When previous viruses happened such as mad cow disease or the swine flu, Australia didn’t ban non-citizens from Britain and the US. Nor was the blame placed on the people in [those countries].
“Since the coronavirus outbreak it has been coined that this virus is the fault of Chinese people, not just in mainland China, but really all over the world.”
Source:, SCMP
Posted in Academic year, Asian Australian Alliance, Australia, Australia’s, Australian Bureau of Statistics, Australian National University (ANU), ‘We’re like cash cows’, Britain, bush fires crisis,, Chinese, Chinese Australians, coronavirus, enrol, immediate family members, Jiangsu, Lunar New Year holiday, mainland, Mainland China, Monash University, non-citizens, permanent residents, Philippines, Prime minister, Scott Morrison, Shanghai, Singapore, stranded, students, Students’ Representative Council, Tourism Research Australia, tourism sector, Tourism Tropical North Queensland, travel ban, Uncategorized, United States, university, University of Sydney, University of Technology Sydney, upset, US, WeChat, Wuhan |
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