CAMBRIDGE, United Kingdom — Fur farms filled with carnivores, such as minks, may become a breeding ground for new pathogens and diseases that conceivably could cross over to humans one day, a new study warns. Researchers from the University of Cambridge report that carnivorous animals lack certain key genes responsible for recognizing and reacting to new pathogenic infections.
This suggests that placing large numbers of carnivores huddled together, which is exactly what happens to farmed animals, would facilitate the creation of under-the-radar “disease reservoirs.” Such an occurrence would provide the perfect opportunity for a new pathogen to fester, mutate, and eventually develop into a human health concern.
A genetic weakness in carnivores?
The team at Cambridge say carnivores have a defective immune system, making them very likely to asymptomatically carry various disease-causing pathogens. More specifically, researchers discovered three important genes for gut health that lost their function in carnivores. If those genes did work, they would produce protein complexes called inflammasomes in response to pathogens that would activate inflammatory responses and ultimately fight off said pathogens.
A carnivorous diet is, of course, very high in protein. Beyond that, though, study authors theorize antimicrobial properties of most carnivore’s diets may be enough to “compensate” for the loss of those three genes. In other words, any pathogen in a carnivore’s stomach is likely to leave the body through diarrhea. That’s all well and good, but it doesn’t stop pathogens from hiding out within other bodily areas.
“We’ve found that a whole cohort of inflammatory genes is missing in carnivores – we didn’t expect this at all,” says senior study author Professor Clare Bryant in the University of Cambridge’s Department of Veterinary Medicine, in a media release. “We think that the lack of these functioning genes contributes to the ability of pathogens to hide undetected in carnivores, to potentially mutate and be transmitted becoming a human health risk.”
Spreading viruses to humans
Zoonotic pathogens often reside within animal hosts before making the jump to humans. While the exact origin of COVID-19 remains a mystery and highly politicized, it’s possible that SARS-CoV-2 (the virus responsible for COVID-19) originated at some point within a wild animal. Suffice to say, this report is equal parts chilling and concerning in its implication that another pandemic may one day shake the world by its very foundation.
Researchers list minks, cats, and dogs as the carnivores generally believed to be the biggest carriers of zoonotic pathogens.
“When you have a large population of farmed carnivorous animals, like mink, they can harbor a pathogen – like SARS-CoV-2 and others – and it can mutate because the immune system of the mink isn’t being activated. This could potentially spread into humans,” Prof. Bryant concludes.
Study authors made it a point to mention that their work by no means suggests cats or dogs are capable of carrying or transmitting COVID-19. This work speaks specifically to what may occur when a large collection of carnivores enter a small, confined setting.
The study appears in the journal Cell Reports.