Thread by @soniashah

My latest for @NYTMag--on the under-covered phenom of "spillback," by which human pathogens cross the species barrier into the non-human world--is out!

tinyurl.com/3vs4mmr6

To write it, I spent >6 months following #SARSCoV2 as it radiated from humans into non-human animals.

Which drew me into the strange & secretive world of the modern fur trade: a $20 billion industry that traffics in the skins of carnivorous mammals.

tinyurl.com/3vs4mmr6

Such as Neovison vison, the American mink.

Scientists have known that mink are vulnerable to coronaviruses since the first SARS outbreak in 2002-3. Yet the factory farming of mink has continued in Europe, the US, China and elsewhere

Mink farming introduces unique risks.

Minks are not sociable herd animals like cows, sheep, chickens & pigs, who have been under human domestication, exchanging microbes back and forth with each other & with us, for thousands of years.

They are solitary, meat-eating predators

Once we infected them with SARS-CoV-2, an est. 7 million mink on 400+ farms in Europe & North America sickened. >700k died, a toll orders of magnitude greater than that borne by any other nonhuman species.

(Not to mention millions of healthy mink who were proactively "culled.")

The mink outbreak brewed at least 3 variants that emerged in humans:

Cluster 5, Marseille-4 & the Michigan mink variant, detected in a taxidermist w/ no known links to mink

No evidence that Omicron came from mink, tho' some think that it may have evolved in an animal host

Despite passive and piecemeal surveillance of wildlife, scientists detected SARS-CoV-2 in 2 free-living species as well: wild mink & white-tailed deer.

These creatures could establish a new wildlife reservoir--or spread it to others who will

tinyurl.com/3vs4mmr6

Or to endangered species.

Like black-footed ferrets, which are the most endangered mammal in the continent.

They're mustelids like mink.

In Utah, 2 mountain ranges separate their habitat from mink farming areas, but mink have been seen around ferret territory in SD and WY

I.e.--this common depiction of the spread of pathogens across species suggests that humans are at the center of the process, but we're not.

Take morbillivirus, which we likely acquired from cattle in whom it's called rinderpest.

Europeans spread morbillivirus to people in the New World, whose measles-infected bodies were likely scavenged by dogs.

(This is a really cool paper btw)

sciencedirect.com/science/articl…

Here's an illustration from the 16th-century accounts of the Spanish priest Bartolomé de Las Casas, depicting conquistadors feeding native children to dogs

In 1735, morbillivirus broke out in dogs in Ecuador and Peru.

It's now a major pathogen of dogs, causing the disease known as distemper.

And that connects back to mink farms!

To control distemper in mink, mid-20th century farmers used a vaccine consisting of ground-up spleens from distemper-infected mink.

That concoction included a vaccine-resistant pathogen known as amdoparvovirus-1

which has since spread through the mink trade to farms around the world

it's also been found in 41 percent of wild adult mink & nearly 4 percent of martens in British Columbia, & in more than a quarter of striped skunks in California

it can infect humans too.

These pathogens regularly leak out. Biosecurity measures at mink farms, I found, was less than ideal

Some mink farms I visited in UT didn't even have complete perimeter fencing

& the mink sheds have no doors bc of their strong odor (they're related to skunks, so)

Some are located in the middle of neighborhoods; I spoke to neighbors who complained about the stench and about escaped mink terrorizing their pets and backyard chickens

tinyurl.com/3vs4mmr6

I saw feral cats slinking in and out of open farm gates. Flocks of gulls circling overhead. A family of turkeys on one farm lot. I saw deer on one mink farm property, and nearby roadway signs warning of deer crossings at others.

tinyurl.com/3vs4mmr6

Fortunately, there's a Covid vaccine for mink.

But at least one farmer I spoke to had no plans to use it.

(I asked if I could take his pic, and he posed by holding this shrieking mink up toward his face)

In most states, there are no regulations on mink farms.

& yet US public health officials did no active surveillance--they relied on mink farmers to self-report outbreaks.

"It's not that different," said @bahanbug "from these captive wildlife farms that we hear about in Asia"

True--but I didn't have the police called on me when I reported on wet markets in China. I did in Utah.

The fur industry even issued a "security alert," warning its members not to let me onto their property, replete w/a pic of my car & license plates

That's me, the "reporter"

After the mink outbreaks in Europe, a dozen countries banned or phased out fur farming. Austria & Netherlands aim to end fur farming in the EU.

But here, efforts to ban mink farming failed in Oregon, & a bill to ban mink farming introduced in July languishes in Congress.

Why?

The mink industry is just a faint shadow of the fur trade that spawned it centuries ago. Today it mostly sells pelts as luxury jackets & fur-trimmed sweaters to consumers in Asia.

But it still leverages the hefty political influence of the American livestock industry.

We need to rethink Covid-19, not just as a human pandemic, but as a multispecies event.

Bc we are animals among animals. By engineering strange & intimate encounters betw infected creatures we endanger our fellow species & implicate our own bodies too.

tinyurl.com/3vs4mmr6