Minks, like humans, often die of infection with the virus, and no one knows why. “This is a key thing,” said Dr. Perlman. “Why do people get sick? Why do we react so differently to these viruses? “He said he had considered studying mink, but the challenges surrounding their genetic diversity and the lack of established biochemical tools to study infections in them made the prospect difficult.
Dec. 26, 2020, 12:08 p.m. ET
Some pieces of the mink puzzle fit together easily. They live in rows of cages on mink farms in crowded conditions, like people in cities, and are in constant contact with the people who care for them. So it’s no wonder that they not only caught the virus from humans, but returned it to us.
Mink infection and the potential danger they pose are a reminder that spill-over events are not only caused by wild animals. The cattle people, housed in a confined space, have always given humans diseases and acquired diseases from them. But it required large human settlements for epidemics and pandemics to occur.
In a 2007 article in Nature magazine, several infectious disease experts – including Jared Diamond, the author of “Guns, Germs, and Steel: The Fate of Human Societies” – wrote about the causes of diseases that only occur in relatively dense human societies Spread populations. Measles, rubella and pertussis, they wrote, are examples of mass diseases that require several hundred thousand people to spread sustainably. Human groups of this size did not appear until before the advent of agriculture about 11,000 years ago.
The authors listed eight diseases of temperate regions that passed from domestic animals to humans: “Diphtheria, influenza A, measles, mumps, pertussis, rotavirus, smallpox, tuberculosis”. In the tropics, more diseases came from wildlife for a variety of reasons, the authors wrote.
Diseases migrate from wild animals to farm animals and then to humans. Influenza viruses jump from wild waterfowl to domestic birds and sometimes to pigs and then to people who are in close contact with the breeding animals. As with the mink, the viruses continue to mutate in other animals.
There may even have been a previous coronavirus epidemic that came from cattle. Some scientists have speculated that one of the coronaviruses that is now causing the common cold, OC43, could be responsible for the 1889 flu epidemic that killed a million people.