US virus researchers kept in the dark
CDC did not make timely disclosures on suspected mink-to-human COVID transmission in 2020
The reputation of the US Centers for Disease Control and Prevention has been called into question after the revelation that thousands of government documents suggest that it delayed releasing information about the first animal-to-human transmission of COVID-19 on a Michigan fur farm in 2020.
The documents obtained under the Freedom of Information Act, initially by National Geographic last month, include emails between Michigan public health officials and the CDC that appear to show evidence that the CDC did not update its website for three months with a public announcement after it first discovered at least two cases.
Critics say that the CDC should have revealed the information immediately as it was “dangerous” not to keep scientists informed as they carefully documented how the virus was mutating and could affect humans.
Jim Keen, director of Veterinary Sciences at The Center for a Humane Economy, an animal welfare organization in Bethesda, Maryland, told China Daily: “Well, it was potentially dangerous, (not to release information immediately) because again, at that time, there was no vaccine and the situation in mink was relatively new, it was known to be moving through the European nations at that same time.
“In some ways, I would even say it was unethical, because one of the principles of public health is to report outbreaks immediately,” said Keen, a former employee of the United States Department of Agriculture, or USDA.
“And I don’t know why they didn’t do that … you’re not supposed to hide that health information, especially from the public health community. And… certainly not from the public.”
Lynn Sutfin, a spokesperson for the Michigan Department of Health and Human Services, confirmed that Michigan officials invited four veterinary epidemiologists from the CDC to the fur farm in October 2020. They carried out tests to detect coronavirus in the mink and employees on the farm after the state reported an outbreak there.
Sutfin told China Daily: “As part of a One Health investigation into a Michigan mink farm with SARSCoV-2 in people and mink in Michigan, specimens were collected and tested from mink farm employees and mink on the farm in October 2020.”
By Nov 4, 2020, after sequencing the specimens, the CDC made an extraordinary discovery. The samples from the two mink farm employees showed that they had not only tested positive for COVID-19, but the virus mutations that were present in the samples also came from mink on the farm. It indicated that the first minkto-human transfer of COVID-19 had occurred in the US.
Months later, a further two people, a taxidermist and his wife, who lived in the same house in Eaton County, Michigan — but were not employees of the mink farm — tested positive in December 2020 and February 2021 with the same genetic mutations as those seen in the mink farm employees.
Sutfin added: “The mink were initially found to be infected and the human case investigation occurred after the mink were found to be infected.
“CDC and Michigan Department of Health and Human Services Bureau of Laboratories sequenced viral genetic material from these specimens, which showed that two farm employees who tested positive for COVID-19 had sequences containing two virus mutations (F486L and N501T) that were also present in sequences from mink on the farm.”
Shortly after the findings, the state’s agriculture department said in a statement: “There is currently no evidence that animals, including mink, play a significant role in spreading the virus to humans in Michigan.”
What the CDC did next raised questions among public health experts and veterinarians.
While the agency knew that the two Michigan farmworkers’ virus genomes had the mink-associated mutations by Nov 4, 2020, it was not until March 2021 that it updated its website with the information.
The CDC did not respond to two separate requests from China Daily to clarify why this occurred. Until January 2021, the CDC told National Geographic that there was “no evidence of mink-to-human spread in the US”.
Nick Spinelli, a CDC spokesman, denied to National Geographic that the CDC’s findings were delayed or kept private. He said, instead, that the genomes of those four virus samples were uploaded to GISAID, a public global coronavirus database, between Nov 4, 2020, and Feb 23, 2021. By December, the third case’s genome was uploaded to GISAID.
Yet, this database requires users to register for an account and unravel complex genome sequence mapping. Two public health experts confirmed to China Daily that they had been unable to access the database, despite both having decades of experience in their field, so the evidence remains unseen by much of the public.
A mink-to-human transmission of COVID-19 had never been officially recorded in the US, but, internationally, mink-to-human spread of COVID-19 had been reported and confirmed in the Netherlands and Denmark.
Public health experts believe that the information in GISAID on outbreaks containing the spike protein Y453F in Michigan and Wisconsin would have also likely remained hidden from public view were it not for two Canadian researchers who had GISAID access and downloaded complex
sequencing from it on March 12, 2021.
Scott Weese, director of the Centre for Public Health and Zoonoses at the University of Guelph, in Canada, believes that it was important for the CDC to report outbreaks immediately to keep the global public health community informed and safe.
Weese told China Daily: “The other aspect, though, is international communications because this pandemic doesn’t respect boundaries. We learn a lot by seeing what happens in other countries. If we don’t hear about what’s happening, we can miss opportunities to intervene. So, failure to spread the information to public health colleagues internationally could have had a negative impact.”
Michigan has 12 mink farms with about 22,000 animals, according to 2017 data from the USDA.
The only other cases of animal-tohuman transmission of COVID-19 have involved a pet hamster in Hong Kong and a white-tailed deer in Canada.
Across the US, the USDA has recorded 18 COVID-19 outbreaks on 60 mink farms. At least 12 occurred in Utah, three in Wisconsin, one in Oregon, one in Michigan and one in another unidentified location. It is not known if there have been more.
On most fur farms, thousands of furry, small mink live in crowded, often caged conditions. Their manure piles up beneath their cages, making any viruses that arise easy to transmit. It will go from mink-to-mink first and then spread to other animals. If there is a virus outbreak, it comes out through the mink’s breath or through their waste.
Mink farms have been branded “the perfect breeding ground” for infectious disease as they can contract COVID-19, similar to humans, because their cells have a protein called ACE2 that allows the virus to easily enter their bodies and multiply.
The American Rescue Act, 2021, legislation passed for COVID-19 relief, included $300 million to the USDA Animal and Plant Health Inspection Service for animal surveillance and monitoring of COVID-19. However, no details have been released on investigations into captive mink, mink surveillance or how mink spread COVID-19.
The CDC and the USDA currently decide along with state health departments when animals should be tested for COVID-19 if they show signs of infection.
Wayne Pacelle, president of Animal Wellness Action, a nonprofit in Washington, DC, told China Daily that mink farms in Europe and the US have spawned five deadly COVID-19 variants.
“These are the only confirmed cases of spillover of COVID-19 variants from animals to people. Unless we shut down mink farms, other variants will almost certainly emerge and threaten human health and the global economy,” Pacelle said.
The US mink industry was valued at $47 million in 2020. The top mink-producing state is Wisconsin, with approximately 19 farms that kill 400,000 mink a year.
Since April 2020, COVID-19 outbreaks have affected more than 450 mink fur farms in Europe and North America, resulting in over 20 million animals being culled, according to The Fur Free Alliance, an international coalition of animal protection organizations covering 35 countries.
In many European nations, the reporting of a virus outbreak among animals is mandatory and they are obligated to tell the public health authorities when an outbreak occurs. In the US, it is optional.
In 2020, Denmark, then the largest mink producer in the world, and the Netherlands killed millions of mink over fears that they could spread COVID-19.
In another step, lawmakers in the Netherlands, a major mink breeder, voted to outlaw mink farming. Ireland passed legislation in March to ban fur farming.
Keen at The Center for a Humane Economy said he has recorded five dangerous farmed mink mutant strains that have later infected people. They include: Cluster 5 in Denmark and the Netherlands, Marseille-4 in France, N501T in Michigan, Y453F in Poland and lastly Latvia, which discovered a mutant mink strain that eventually infected both humans (employees on a farm) and mink.
He warned that there will likely be more COVID-19 mutations among mink that could affect humans, strain COVID-19 vaccines, and “risk a catastrophic outcome”, if nothing changes in the US industry.