Some panthers and bobcats in Florida have been acting strangely lately, and it’s gotten the attention of state wildlife officials. The big cats are walking abnormally and are having extreme difficulty controlling their hind legs, and experts are struggling to determine the cause.
Trail footage from counties of the west coast of southern Florida shows the animals struggling to walk. They appear to have no trouble using their front legs, but their hind legs crisscross and sometimes completely give out under their weight as they walk, causing them to stumble and struggle to continue walking. The video footage has shown eight panthers (mostly kittens) and an adult bobcat that appears to have the same condition.
“We have not seen anything like this in wild panthers or bobcats in Florida before,” said Florida Fish and Wildlife Conservation (FWC) spokeswoman Carli Segelson told Fort Myers News-Press in an email.
One panther and one bobcat that were tested showed positive signs of neurological damage.
Wildlife officials say the animals are struggling with “coordinating their back legs.”
“While we do not know what is causing the abnormal gait, possible causes include a variety of toxins and infectious diseases, many of which have been ruled out,” Segelson said. “The affected animals that we have had in hand have not had distemper.”
Several videos of affected cats were collected from Lee, Collier, and Sarasota counties. FWC believes at least one cat in Charlotte is also suffering from the condition.
“The number of animals exhibiting these symptoms is relatively few; however, any disease or condition impacting multiple animals is cause for concern,” Segelson explained. “We are increasing monitoring efforts to determine the full scope of the issue.”
The FWC is now testing the cats for additional toxins, including rat poison, along with other possible infectious diseases and nutritional deficiencies. They have not shared the eliminated conditions with the public as of the time of this writing.
In a news release, the FWC asked the public to submit any video footage of photos “that happen to capture animals that appear to have a problem with their rear legs” to their panther sighting webpage at MyFWC.com/PantherSightings. If you have larger files, they ask that you please contact the FWC at [email protected].
Here is some video footage of affected panthers:
There is one possible cause that isn’t being mentioned.
I’ve been scouring the internet in search of information on this, and as of the time of this writing, I have been unable to find any discussion on one possible cause of this strange big cat behavior: prion disease.
Recently, we reported on the rise in cases of a prion disease called Chronic Wasting Disease (CWD, also referred to as “Zombie Deer Disease”) in cervids. The symptoms in the panthers and bobcats in Florida sound similar, so I did some digging to see if this kind of disease infects cats.
It turns out, it does. It is called Feline Spongiform Encephalopathy (FSE) and it is a neurodegenerative disease, caused by a prion, that affects members of the cat family. According to a report from The Center for Food Security and Public Health at Iowa State University,
Once the clinical signs appear, this disease is invariably fatal. FSE is caused by the same agent that is responsible for bovine spongiform encephalopathy (BSE) in cattle.
FSE has been documented in domesticated cats (housecats) and captive wild cats including cheetahs (Acinonyx jubatus), pumas (Puma [Felis] concolor), ocelots (Leopardus [Felis] pardalis), tigers (Panthera tigris), lions (P. leo), an Asian golden cat (Catopuma temminckii) and an Asian leopard cat (Prionailurus [Felis] bengalensis). (source)
An early sign of prion disease in animals is problems with walking – in particular, issues with hind legs. This has also been noted in felines with prion disease:
Gait abnormalities and ataxia are also common, and typically affect the hindlegs first. Affected cats often display poor judgment of distance. Some cats develop a rapid, crouching, hypermetric gait. (source)
Prion diseases are characterized by sponge-like holes in brain tissue. They are notoriously difficult to diagnose, untreatable, and ultimately fatal. Prions are very difficult to kill.
Prions are known to cause disease in animals and humans.
Prions are abnormally folded proteins that lack DNA. They spread through tissue like an infection and replicate by causing other normally folded proteins to rearrange themselves into a misfolded structure. The misfolded proteins accumulate in the brain, eventually leading to tissue damage and resulting in neurological clinical signs and deficits.
“Prion disease epidemics are frequent, and, since they are invariably fatal and incurable, of significant concern for animal and human health. Increasing evidence also links the prion mechanism to proteins involved in the pathogenesis of other common neurodegenerative diseases including Alzheimer’s and Parkinson’s diseases,” according to the Prion Research Center (PRC) at Colorado State University.
According to the PRC, prions are “distorted versions of normal proteins found in human and animal brain and other tissues”:
These distorted (‘misfolded’) proteins damage brain cells, leading to fatal dementias akin to human Alzheimer’s and Parkinson’s diseases. One of the amazing things about prions is that, although they are composed only of proteins and contain no genes, they have acquired the ability to be transmitted like other infectious agents such as viruses or bacteria.
Best known prion diseases are mad cow disease of cattle and humans, Creutzfeld-Jakob disease of humans, chronic wasting disease of deer and elk, and scrapie of sheep. Better understanding of prions is important in controlling the threat they represent to animals and humans and for what we can learn about the cause and treatment of the major dementia diseases of humans. (source)
Other protein misfolding diseases include Lou Gehrig’s disease and Huntington’s disease.
Earlier this year, a study found that two proteins central to the pathology of Alzheimer’s disease act as prions:
Using novel laboratory tests, the researchers were able to detect and measure specific, self-propagating prion forms of the proteins amyloid beta (Aß) and tau in postmortem brain tissue of 75 Alzheimer’s patients. In a striking finding, higher levels of these prions in human brain samples were strongly associated with early-onset forms of the disease and younger age at death.
Alzheimer’s disease is currently defined based on the presence of toxic protein aggregations in the brain known as amyloid plaques and tau tangles, accompanied by cognitive decline and dementia. But attempts to treat the disease by clearing out these inert proteins have been unsuccessful. The new evidence that active Aß and tau prions could be driving the disease – published May 1, 2019 in Science Translational Medicine — could lead researchers to explore new therapies that focus on prions directly.
“I believe this shows beyond a shadow of a doubt that amyloid beta and tau are both prions, and that Alzheimer’s disease is a double-prion disorder in which these two rogue proteins together destroy the brain,” said Stanley Prusiner, MD, the study’s senior author and director of the UCSF Institute for Neurodegenerative Diseases, part of the UCSF Weill Institute for Neurosciences. (source)
Prion diseases or transmissible spongiform encephalopathies (TSEs) are a family of rare progressive neurodegenerative disorders that affect both humans and animals. These diseases are distinguished by long incubation periods, characteristic spongiform changes associated with neuronal loss, and a failure to induce an inflammatory response.
The causative agents of TSEs are believed to be prions, the CDC explains:
The term “prions” refers to abnormal, pathogenic agents that are transmissible and are able to induce abnormal folding of specific normal cellular proteins called prion proteins that are found most abundantly in the brain. The functions of these normal prion proteins are still not completely understood. The abnormal folding of the prion proteins leads to brain damage and the characteristic signs and symptoms of the disease. Prion diseases are usually rapidly progressive and always fatal. (source)
According to the CDC, prions can cause the following:
- Creutzfeldt-Jakob Disease (CJD)
- Variant Creutzfeldt-Jakob Disease (vCJD)
- Gerstmann-Straussler-Scheinker Syndrome
- Fatal Familial Insomnia
- Bovine Spongiform Encephalopathy (BSE, also known as Mad Cow Disease)
- Chronic Wasting Disease (CWD)
- Transmissible mink encephalopathy
- Feline spongiform encephalopathy
- Ungulate spongiform encephalopathy
How are prion diseases transmitted?
Prion diseases can be inherited, acquired by infection, or arise spontaneously without a known cause, the PRC explains:
In humans, prion diseases are predominantly due to sporadic causes and are rarely transmitted between individuals. The most common types of human to human transmission are related of medical procedures involving transfer of tissues from a human with an undiagnosed prion disease. These mainly include recipients of growth hormone therapy and tissue grafts from the fibrous covering of the brain. There have been a few cases of human prion disease related to blood transfusion in the United Kingdom. These cases were related to a human prion disease that was acquired from cattle with bovine prion disease. This is a rare disease in humans that is disappearing due to preventative public health measures. In animals the most important prion diseases result from infectious transmission. In the USA, chronic wasting disease of deer and elk is the most readily transmitted of the prion diseases. (source)
In 2015, a study found evidence for human-to-human transmission of the prions that underlie the pathology of Alzheimer’s disease.
There is currently no cure for prion diseases.
There’s a lot of research being conducted on prions and preventing and curing related diseases. New research suggests skin samples hold early signs of prion disease that precede neurologic symptoms, and scientists are hoping that the detection of skin prions will be useful for monitoring disease progression and assessing therapeutic efficacy during clinical trials or treatments when prion therapy becomes available in the future.
Some studies have found that prions appear to thrive and grow when pH levels are low (acidic conditions). It is possible that altering pH levels may prevent prions from aggregating or growing into deadly diseases.
Scientists are also studying the use of antisense oligonucleotides (ASOs), synthetic compounds that inhibit the formation of specific proteins, to slow the progression of prion diseases.
And, a product called BrioHOCl that mimics the natural oxidative killing action of human immune cells against bacteria, viruses, and fungi may also inactivate prions and other proteins. BrioHOCL is ahighly purified formulation of hypochlorous acid, which immune cells produce naturally to kill microbes.
One study on BrioHOCL showed promise:
The scientists determined that BrioHOCl eliminated all detectable prion-seeding activity for CJD, bovine spongiform encephalopathy (BSE, or mad cow disease), chronic wasting disease (a disease primarily found in deer, elk, and moose) and scrapie (a disease of sheep) in brain tissue. They conducted a portion of the study using stainless steel wire as a surrogate for surgical instruments. BrioHOCl had similar effects on two proteins thought to contribute to Parkinson’s disease and Alzheimer’s disease. (source)
For now, preventing infection with prion disease seems like the best option, but even that seems difficult to do.
Hopefully, prion disease is not what is infecting panthers and bobcats in Florida. Perhaps it is a curable – or less fatal – disease that is impacting them. Time will tell.
What do you think?
Do you think that prion disease could be what is infecting panthers and bobcats in Florida? If not, are there other possible causes that you can think of? Are you concerned about prion diseases? Please share your thoughts in the comments.
About the Author
Dagny Taggart is the pseudonym of an experienced journalist who needs to maintain anonymity to keep her job in the public eye. Dagny is non-partisan and aims to expose the half-truths, misrepresentations, and blatant lies of the MSM.