Coronavirus is mutated in mink and “transmitted” to humans. Will it affect the effect of vaccine?
Earlier this month, Denmark decided to culminate 17 million farmed minks across the country. Researchers discovered that after the Coronavirus spread from humans to farmed minks, the virus mutated and then “passed back” to humans. The WHO said on November 7 that this preliminary survey result has global significance.
Due to the lack of legal basis, the Danish government withdrew the “culling order” on November 10 and changed the mandatory order to a recommendation. Thousands of minks escaped temporarily, but the potential threat they brought is still approaching.
According to a CNN report on the 10th, as the world’s largest mink exporter, more than 230 mink farms in Denmark have experienced Coronavirus pandemic, and 12 people have been found to be infected with a mink-related mutant virus. In addition to Denmark, the Netherlands, Spain, Italy, and the United States have all reported mink infections to the WHO.
Danish Minister of Health Magnus Heunicke said on November 4: “Research shows that virus mutations may affect existing vaccine candidates for Coronavirus.” WHO pointed out when talking about mink infection at a press conference on the 6th. “Although Coronavirus Pandemic is considered to be related to bats, the origin and intermediate host of SARS-CoV-2
(Note: the Coronavirus is named SARS-CoV-2 and the disease is named COVID-19) has not been confirmed.” Conclusion, whether this mutant virus will affect the vaccine.
Lucy van Dorp, a senior researcher at the UCL Genetics Institute at University College London (UCL Genetics Institute), told The Paper that the new coronavirus that has been mutated in mink may behave differently after it is transmitted to humans. The possibility of the virus becoming more infectious and serious is not ruled out, but current research shows that it does not pose a higher risk to humans.
The “reservoir” of the new coronavirus
Since the outbreak of the Coronavirus pandemic, animal infections have been common. The United States discovered that a shepherd dog died after being infected with Coronavirus in June; the Netherlands, France, Belgium and other countries have successively found cats infected with Coronavirus; the Bronx Zoo in New York, the United States reported that 4 tigers and 3 lions tested positive for Coronavirus in April; Mink was also “successful”.
In April this year, two mink farms in the Netherlands reported Coronavirus pandemic and found that the mink had signs of respiratory disease and some died. About a month later, the Dutch government website issued a statement on May 19 stating that after investigating mink farms, the results showed that Coronavirus virus can be transmitted from mink to humans, and there has been the world’s first case of human infection caused by mink.
Before long, a test of nearly 100,000 minks on a farm in Spain showed that the positive rate for Coronavirus reached 87%. Prior to this, seven workers on the farm were diagnosed. According to the “Guardian” report on July 17, all minks were culled from farms in Spain where the pandemic occurred, and the number of minks culled in several farms in the Netherlands reached one million.
The American academic journal “Science” published a paper from the Dutch scientific research team on November 10, through genomic analysis of the mink and related human Coronavirus cases from 16 Dutch farms, and found that Coronavirus virus can be between humans and minks. The conclusion of two-way communication.
Six countries have successively reported incidents of mink infections, among which Denmark has the largest outbreak. According to the British Broadcasting Corporation (BBC), Denmark, with a population of about 5.8 million, has a total of about 17 million mink farms. Starting in August, the first case of mink infections appeared in Denmark. As of November 11, one-fifth of the country’s farms had reported an pandemic, and more than 200 people were infected with mink.
Kare Molbak, director of the Danish National Serum Institute (Statens Serum Institut), said in an interview with Danish media Politiken recently that minks are particularly susceptible to the Coronavirus, and large numbers of them are raised in Denmark. “Once one is infected, the virus is like The speed of light spreads.” He reminded that mink has become a “reservoir” for Coronavirus in Denmark.
The mink infection incident has caused concern in many European countries. The British government announced on November 7 that all non-British citizens from Denmark are prohibited from entering the country. British citizens entering Denmark are required to self-quarantine for 14 days.
Will the mutated virus invalidate the vaccine?
In view of the severe pandemic prevention situation, the Danish government ordered the culling of all farmed minks in the territory on November 3. “This is very, very serious.” Danish Prime Minister Mette Frederiksen said at a press conference on the 4th that the mutated virus in mink may have “destructive consequences” for the world.
“Mutation is a natural process of virus evolution. Just like SARS-CoV-2 mutates in humans, it also produces mutations in mink.” Lucy Van Dopp explained that most mutations have no functional effect on the virus. However, the new coronavirus has mutated after being transmitted from humans to mink, and new mutations may appear after returning to humans. Such mutations are often beneficial to the new host but not to humans.
According to a report released by the WHO on November 6th, since June this year, a total of 214 people in Denmark have been infected with Coronavirus related to farmed mink, and there have been 5 different mink-related variants, namely cluster 1～cluster 5. Twelve of these infected people carry this variant called “cluster 5,” which is less sensitive to antibodies.
The most worrying is the impact of viral mutations on vaccine development. According to a BBC report on the 10th, Danish virologist Andels Fomsgaard said that the more mutations in the virus, the more difficult it is to fight Coronavirus pandemic. “This may mean that future vaccines will have little or no effect, or that people who have successfully recovered are still not immune.”
Lucy Van Dopp pointed out that mutations in the spike protein of the new coronavirus may eventually evade the effects of the vaccine, but currently this change has only occurred in a very small number of mink and human cases, and the exact impact is still unknown. , It is also necessary to continue testing the genome of the mutant virus to observe more changes.
Scientist Anders Fomsgaard of the Danish National Serum Institute said in an interview with Danish Radio and Television (DR) on the 12th that they injected the rabbit with Coronavirus vaccine under development and extracted antibodies from it. Experiments show that the antibody successfully defeated the “cluster 5” variant. “We don’t know whether other vaccines will have the same effect, or whether this applies to human antibodies.”
A risk assessment report issued by the European Center for Disease Control and Prevention on November 12 pointed out that the potential threat to humans caused by the spread of the new coronavirus through mink and its mutation is still “very uncertain”.
The future of the mink industry
When Denmark was urgently culling mink, the opposition party proposed that the government’s directive lacked a legal basis and the authority only allowed it to culminate infected minks unless a new bill was passed. Danish Prime Minister Frederickson apologized for the matter in Parliament on November 10, “This is a regrettable mistake. Even if we are very anxious, we should know that we need to update the legislation.” The government is trying to implement mandatory legislation through emergency legislation. The opposition party does not support the culling order. It will take at least 30 days to pass a new bill in Parliament.
For Danish mink farm operators, although the government has put a brake on the culling order, they know that the industry is unsustainable. “It’s too difficult for me. This is all we have.” Jepsen, the 34-year-old mink farm owner, told Reuters that the government ordered all minks to be culled within 10 days. “The family business is just ruined, it’s impossible. It’s getting better again.”
The Danish Poultry and Food Administration said on the 10th that 116 mink farms across the country have been culled, and more than 2.85 million mink have been killed in recent weeks. Although the culling order is no longer mandatory, this work will continue.
The latest data released by the Danish Agriculture and Food Commission show that Denmark produces about 19 million mink every year, and the Kopenhagen Fur produced by Denmark’s 1,500 fur farmers accounts for 40% of the world’s total mink production. According to the Associated Press, Denmark’s culling of 15 million minks may cause a loss of 5 billion kronor about 1B USD!
In fact, Coronavirus pandemic has not only brought an almost extinct disaster to Danish mink farming, but the entire European mink industry is also facing a choice. The BBC reported that there are about 4,350 mink farms across Europe, and countries such as Poland, Finland, Lithuania, and Greece all have a share in the mink export industry. The Fur Europe Industry Alliance has so far insisted that demand in the fur market is still very strong.
The Netherlands originally planned to implement a law banning mink farming in 2024. The arrival of Coronavirus pandemic has accelerated the timetable, and the relevant ban will be implemented on March 21, 2021. The French government also announced at the end of September this year that by 2025, it would completely ban mink farming from obtaining mink fur.
Three scholars from China, Denmark and Malaysia recently published a communication article entitled “Prohibition of Unsustainable Mink Breeding” in Science, calling for attention and monitoring of all mustel animals, including ferrets and other fur-breeding animals , Take precautions before they happen.
Xia Changlei, a professor at Nanjing Forestry University, as one of the authors of the above communication article, told The Paper: “In recent years, the continuous emergence of new viruses may be an inevitable product of ecosystem changes. Unfortunately, these viruses (such as Covid-19) ) Preference for animals and wild animals with zoonotic diseases. This may be just the starting point, and the end is far from coming.”