The novel coronavirus can survive for 20 years in temperatures of minus 20 degrees Celsius, a leading Chinese expert has claimed.
Professor Li Lanjuan, a member of China's COVID-19 expert team, said that the virus could easily be transported between countries due to its exceptional abilities to endure cold conditions, according to state media.
The epidemiologist urged Chinese authorities to strengthen the inspection of imported frozen food products, including salmon, to prevent the further spread of the infection.
Prof Li made the comments today at a meeting in Hangzhou, eastern China, reported state-run China News.
She was quoted saying: 'The novel coronavirus is "particularly not afraid of coldness".
'The virus can survive for a few months in minus four degrees Celsius and 20 years in minus 20 degrees Celsius.'
She added: 'This explains why the virus has been discovered several times in seafood markets which had plenty of frozen food. It is possible for the virus to be transported across countries.'
China has pointed the finger at a European coronavirus strain for a new outbreak in Beijing which has infected nearly 200 people in eight days.
The Chinese government yesterday shared the genome data from the latest outbreak, claiming it 'came from Europe' but is different from the virus that is currently spreading there - suggesting it could have been lurking in frozen food for some time.
European salmon producers have played down the link after state media connected the outbreak to chopping boards used to cut up salmon at the Xinfadi food market.
Today's 25 new cases in Beijing bring the total in the last eight days to 183 in the city's worst outbreak since early February.
Tens of thousands of people in the Chinese capital are being tested for the contagion, while neighbourhoods have been locked down and schools closed as authorities battle to contain the cluster.
Five provinces across China have reported a total of 17 coronavirus infections linked to the outbreak in Beijing since June 11, according to official figures.
Those patients were mostly market vendors working at Xinfadi or close contacts with native coronavirus carriers detected in the capital city.
Henan in central China today reported an asymptomatic case of a 50-year-old woman who worked as a vendor at the Xinfadi market.
Eastern province Zhejiang recorded one infection Wednesday of a man, 36, who also worked at the food trading hub.
Hebei province in northern China has found a total of 10 COVID-19 cases linked to the outbreak in Beijing since Tuesday.
South-western province Sichuan reported two infections on June 15 while Liaoning province in north-eastern China recorded three cases between June 13 to June 18.
Zhang Yong of the Chinese Center for Disease Control and Prevention (CDC) said the strain of the virus spreading in Beijing 'is older than the virus currently circulating in Europe'.
Zhang raised the possibility of the virus lurking in imported frozen food or in the wholesale market itself, resulting in similarities to older strains.
But scientists cautioned against making early conclusions on the Beijing cluster.
Ben Cowling, a public health expert at the University of Hong Kong, said 'it is possible that the virus now causing an outbreak in Beijing had travelled from Wuhan to Europe and now back to China.'
But he said the first case has not yet been identified and it may be too late to find out how this outbreak started.
Francois Balloux of University College London said that based on the data shared, there had been local transmission for some time before the outbreak was identified.
'Their position in the tree does not allow to confidently assign a geographic origin to the lineage. They could have originated from essentially anywhere,' he wrote.
Xinfadi supplies more than 70 per cent of Beijing's fresh produce and has been temporarily closed due to the cluster.
Wu Zunyou, chief epidemiology expert at the CDC, had previously said the virus found in Beijing was similar to European strains.
Wu said the strain did not originate from the Chinese capital. 'It must be some people or goods outside of the city that carried it into the market,' Wu said in a state television interview aired on Friday.
'It's unclear who, or what kind of goods, had brought the virus into Beijing.'
Food wholesalers and retail stores in Beijing have stepped up testing on products including meat and seafood since the outbreak began.
State media reported earlier this week that the virus had been detected on chopping boards used to handle imported salmon at the market.
Official media has already opened fire on the 'sinful' salmon industry in Norway, and Beijing supermarkets have removed salmon from their shelves after officials claimed the outbreak could have come from Europe.
However, Norway has denied any link to its salmon industry and experts say it is unlikely that the fish itself would carry the disease.
Low temperatures and high humidity may explain why seafood markets are a source of outbreaks, Wu said, cautioning that further investigation was necessary.
The earliest known cluster of cases was at a seafood market in Wuhan last December, although it is not yet fully clear how the virus first passed to humans.
One Chinese food safety expert said today that it was possible for food and food packaging to be a host of the novel coronavirus.
The comments were made by Li Fengqin, a director at China National Center for Food Safety Risk Assessment, at a press conference in Beijing today. Li said that researchers had detected the virus in the environment, therefore it was possible for the food and food packing material stored in the same environment to be contaminated.
The resurgence came after China had largely brought the virus under control and eased restrictions on movement inside the country.
There are now 293 people ill with COVID-19 in China, the highest number since early May.
Until recently most new cases had been imported by nationals returning from abroad, but Beijing's new cluster has been locally transmitted.
The last seven days have seen 261 new cases across the country, the highest figure since mid-April.
Chinese officials have not reported a new death since April, although there has been much suspicion about the accuracy of the regime's figures.
Beijing had turned into a virtual fortress at the height of the pandemic, with people arriving from other regions or countries required to undergo quarantines.
While international flights are still diverted to other cities to prevent imported cases, other measures had been relaxed in recent months.
However dozens of neighbourhoods are in lockdown again while hundreds of flights in and out of Beijing have been cancelled.
A city transport spokesman said bus service between Beijing and other Chinese provinces would be suspended starting Friday to try to limit the spread of the virus.
Schools in the city have also been suspended and reopening plans for sports and other events are on hold.
One official said on Wednesday that China had carried out more than 350,000 tests in the space of four days.
China had been under pressure to release the genome data after criticism of its initial handling of the outbreak earlier this year.
The US has blamed the Chinese government for not handling the Wuhan outbreak properly and moving too slowly to contain the epidemic, leading to mounting cases and deaths in the United States.
China has rejected that accusation, saying it wasted no time in releasing information about the epidemic including the genome sequence of the initial outbreak.
The latest genome sequencing was published late Thursday, and had been shared with the WHO and the Global Influenza Data Initiative (GISAID).
Virus genome sequencing is a vital and rapidly-developing tool in the diagnosis of the disease and in understanding the spread and control of the new coronavirus.
Details published on China's National Microbiology Data Center website revealed the Beijing genome data was based on three samples - two human and one environmental - collected on June 11.
This article has been adapted from its original source.
© Associated Newspapers Ltd.