Zombie Illnesses: Rabies, Parasites, and Prions
What kind of illness turns deer into stumbling, soulless shells of themselves—bodies wasting away, but never truly dying? Or drives healthy young men into violent frenzies that leave them strapped to hospital beds, terrified of water? This week, we’re diving into the terrifying world of zombie illnesses—real diseases that hijack the brain and erase what makes us human.
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SOURCES
CWD Overview: https://cwd-info.org/cwd-overview/
About TSEs: https://www.ninds.nih.gov/health-information/disorders/transmissible-spongiform-encephalopathies
About CJD: https://www.ninds.nih.gov/health-information/disorders/creutzfeldt-jakob-disease
Chronic Wasting Disease Linked to Ft. Collins for 50 Years: https://www.coloradoan.com/story/news/2018/08/23/cdc-tse-mad-cow-chronic-wasting-disease-linked-fort-collins/878097002/
Eradication of Scrapie progress: https://www.aphis.usda.gov/nvap/reference-guide/control-eradication/scrapie
Scrapie Eradication Program: https://www.aphis.usda.gov/nvap/reference-guide/control-eradication/scrapie
Scrapie Eradication Progress: https://iowaagriculture.gov/sites/default/files/animal-industry/pdf/Scrapie/Scrapie%20Eradication%20Progress%20122120.pdf
CWD Strategies Overview: https://pmc.ncbi.nlm.nih.gov/articles/PMC6778748/
Profile of Beth Williams in High Country Mag: https://www.hcn.org/issues/issue-268/solving-the-puzzle-of-chronic-wasting-disease-veterinarian-beth-williams/
A brief history of prions: https://pmc.ncbi.nlm.nih.gov/articles/PMC4626585/
Study Suggests Hunters Died of CWD: https://gearjunkie.com/outdoor/hunt-fish/study-suggests-hunter-deaths-cwd
Hunters From the Same Lodge Died of CJD abstract: https://www.neurology.org/doi/10.1212/WNL.0000000000204407
Scrapie info: https://www.gov.scot/publications/scrapie/
1997 Nobel Prize release: https://www.nobelprize.org/prizes/medicine/1997/press-release/
CWD distribution: https://www.usgs.gov/media/images/distribution-chronic-wasting-disease-north-america-0#science
Tennessee Wildlife Federation criticizes “hunters with CWD” report: https://tnwf.org/response-to-recent-report-about-cwd/
Fact-checking the viral article about hunters getting CWD from venison: https://www.outdoorlife.com/conservation/hunters-die-eating-cwd-venison/
Rabid fox encounter story: https://www.wral.com/story/encounter-with-rabid-fox-was-scary-experience-for-rolesville-couple/15071237/
Paper mentioning elderly man bitten by bat who died despite receiving rabies post-exposure prophylaxis: https://academic.oup.com/cid/article/77/8/1209/7088993?login=false
Short story about rabies interpreted as “spiritual attack”: https://www.isntd.org/written-journalism/short-story-on-rabies-
Rabies story from person who received vaccine after being bitten by a stray dog: https://citybugs.tamu.edu/2017/01/04/my-rabies-story/
Importance of vaccinating even indoor pets - wildlife can break into the house! https://www.amcny.org/blog/2022/09/21/cautionary-tales-of-rabies-encounters-in-new-york-city/
Last rabies death in Michigan: https://www.detroitnews.com/story/news/local/michigan/2019/10/11/what-happened-last-time-person-died-rabies-michigan/3931347002/
Rabid raccoon report: https://www.lohud.com/story/news/local/westchester/tarrytown/2024/11/08/tarrytown-ny-rabid-racoon-found-westchester-shares-rabies-safety-tips/76110671007/
Soldier sadly dies of rabies after dog bite in Afghanistan: https://www.army.mil/article/78799/redeploying_reserve_component_soldiers_screened_for_rabies
And his family sues: https://www.syracuse.com/news/2012/08/family_alleges_negligence_in_s.html
Potential rabies cure: https://www.yahoo.com/news/potential-rabies-cure-discovered-defense-171713843.html
Potential rabies cure, scholarly version: https://www.embopress.org/doi/full/10.15252/emmm.202216394
Another fox attack story: https://www.wsfa.com/story/31054068/montgomery-county-boy-attacked-by-rabid-fox/
The fox attack story the photo came from: https://www.cbsnews.com/news/fox-attack-woman-upstate-new-york-video/
Rabid fox bit nine people on Capitol Hill: https://www.cbsnews.com/news/fox-capitol-hill-euthanized-after-allegedly-biting-9-people/
More on Capitol Hill rabid fox: https://www.cbsnews.com/news/fox-den-us-capitol-several-aggressive-encounters/
First rabies vaccination: https://www.pasteur.fr/en/research-journal/news/history-first-rabies-vaccination-1885
Pasteur and the rabies vaccine: https://www.cdc.gov/mmwr/preview/mmwrhtml/00000572.htm
Rabies history: https://web.stanford.edu/group/virus/rhabdo/2008/history.html
4000 years of Rabies history: https://pmc.ncbi.nlm.nih.gov/articles/PMC6082082/
Cases of Rabies survival: https://pmc.ncbi.nlm.nih.gov/articles/PMC6335910/
Rabies survival stats: https://www.uptodate.com/contents/treatment-of-rabies/print
Milwaukee Protocol: https://www.aaas.org/taxonomy/term/9/surviving-rabies-now-possible
Jeanna Giese - NBC: https://www.nbc26.com/news/local-news/jeanna-giese-16-years-later-surviving-rabies-to-build-a-beautiful-life
Jeanne Giese interview - Fox: https://fox11online.com/news/local/20-years-later-fond-du-lac-woman-reflects-on-being-1st-to-survive-rabies-without-vaccine-jeanna-giese-bat-centers-disease-control-willoughby-coma-medical-marvel
Scientific American Jeanna Giese story: https://www.scientificamerican.com/article/jeanna-giese-rabies-survivor/
Critical Appraisal of the Milwaukee Protocol: https://www.cambridge.org/core/journals/canadian-journal-of-neurological-sciences/article/critical-appraisal-of-the-milwaukee-protocol-for-rabies-this-failed-approach-should-be-abandoned/8A47C583B24B2B2E43248770F78CC35A
Original case report on Jeanna Giese: https://www.nejm.org/doi/full/10.1056/NEJMoa050382#f01
Jeanna Giese in her own words: https://www.theguardian.com/lifeandstyle/2023/sep/15/experience-i-survived-rabies
CDC on rabies: https://www.cdc.gov/rabies/php/protecting-public-health/index.html
Rabies post-exposure prophylaxis flowchart: https://cdn.who.int/media/docs/default-source/searo/ntd/who-searo-rabies-post-exposure-prophylaxis-decision-tree.pdf?sfvrsn=81239502_1
Minnesota Health rabies Qs: https://www.health.state.mn.us/diseases/rabies/risk/faq.html
Princeton’s Jeanna Giese story: https://paw.princeton.edu/article/survival-story-0
Demise of the Milwaukee Protocol: https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaf157/8096457?searchresult=1
Brazilian indigenous child Milwaukee Protocol failure: https://virologyj.biomedcentral.com/articles/10.1186/s12985-024-02536-2
Merck Manual on Rabies: https://www.merckmanuals.com/home/brain-spinal-cord-and-nerve-disorders/brain-infections/rabies#Symptoms_v8544912
Bat Lyssaviruses: https://wwwnc.cdc.gov/eid/article/26/7/19-1016_article
Last of Us Fungus FAQ: https://www.hackensackmeridianhealth.org/en/healthu/2023/02/16/zombie-fungus-from-the-last-of-us-is-it-real#:~:text=Humans%20cannot%20carry%20the%20fungus,temperatures%20of%20the%20human%20body.
Yale on rising fungal pathogens: https://medicine.yale.edu/news-article/the-last-of-us-apocalypse-is-not-realistic-but-rising-threat-of-fungal-pathogens-is/
Could the zombie fungus really infect people: https://www.scientificamerican.com/article/could-the-zombie-fungus-in-tvs-the-last-of-us-really-infect-people/
NPR on cordyceps: https://www.npr.org/2023/01/30/1151868673/the-last-of-us-cordyceps-zombie-fungus-real
Ants and fungus - gross pix warning: https://www.npr.org/sections/thetwo-way/2012/05/02/151890185/zombie-ants-and-the-fungus-that-saves-them
Candida auris overview: https://academic.oup.com/mmy/article/62/6/myae042/7700339
Turkish case report of toxo: https://www.pbsciences.org/fulltext/8-1592055529.pdf?1744095512
NIH on toxo: https://www.ncbi.nlm.nih.gov/books/NBK563286/
Link between toxo and psychosis/mental illnesses: https://link.springer.com/chapter/10.1007/978-3-030-86811-6_2
Skeptical take on behavioral effects of toxo: https://journals.asm.org/doi/10.1128/mbio.02164-19
Effects of toxo on behavior/mood: https://www.stanleyresearch.org/patient-and-provider-resources/toxoplasmosis-schizophrenia-research/effects-t-gondii-on-behavior-and-psychiatric-symptoms/
Laboratory infection with toxo: https://pmc.ncbi.nlm.nih.gov/articles/PMC479851/
Successful treatment with clindamycin: https://pmc.ncbi.nlm.nih.gov/articles/PMC3472581/
Toxo overview: https://my.clevelandclinic.org/health/diseases/9756-toxoplasmosis
Public health surveillance and reporting: https://www.cdc.gov/mmwr/volumes/71/wr/mm7128a1.htm
TRANSCRIPT
On Sunday morning, September 12th, in 2004, 15-year-old Jeanna Giese (Geena gee-zee (like easy)), of Fond du Lac, Wisconsin was attending mass with her family when she heard something start softly thumping against the stained glass next to her. It was a tiny, brown bat and It seemed to be trying to get back outside. Soon, everyone in the church watched as it flew above their heads, trying desperately to find its way out of the door that it came in through, to no avail.
Finally, someone managed to knock the poor bat to the ground, Jeanna knew she had to help. With her mom’s permission, she scooped up the bat in her hands and ran it outside. It was terrified, making high-pitched squealing noises. But she held it tight, just a few more moments before she could place it gently on a tree and it would be able to find its way home.
But as she went to place the bat down, it opened its little mouth, showing its razor sharp teeth, and bit down on her finger.
OUCH! Jeanna pulled her hand away, looking at the small bloody indent on her hand. It hurt worse than it looked, it was so tiny, it had barely broken the skin.
So Jeanna didn’t think much of it—nor did her mother when she showed her the wound back in the church.
Little did they know, this was the worst possible thing they could have done
Three weeks later, Jeanna’s mom called her down for breakfast, but the girl was so tired she couldn’t get out of bed. The lethargy continued over the next few days, getting worse and severely confusing her family. They took Jeanna to a neurologist, who seemed pretty concerned. Based on her symptoms, she was tested for meningitis and lyme disease, but even though everything tested negative, she continued to get worse, and eventually She was hospitalized at St. Agnes Hospital in her hometown.
By this time, Jeanna was vomiting and had double vision. Her face was flushed. And then, she started slipping in and out of consciousness. Everyone wracked their brains, trying to figure out how a formerly healthy teenager got so sick.
That’s when Jeanna’s mother finally remembered the bat. She told one of Jeanna’s pediatricians, and asked if that could have had anything to do with her daughter’s strange symptoms.
And the doctor immediately went pale, and his eyes got really wide and almost…sorrowful. He had to break terrible news to Jeanna’s parents: bat bites are the most common way humans are exposed to rabies in the United States. And rabies, without immediate treatment, is 100% fatal.
The only hope for a human bitten by a rabid animal is what’s known as “post-exposure prophylaxis,” which combines vaccination and other immune treatments. But, by the time symptoms appear, it’s too late. And Jeanna was already very, very sick.
Doctors transferred Jeanna to the Children’s Hospital of Wisconsin for specialized testing. Rabies antibodies were detected in her cerebrospinal fluid, confirming the diagnosis everyone dreaded. Jeanna had rabies. The disease was slowly taking over her brain, and She was going to die.
Welcome back to heart starts pounding, Im your host, Kaelyn Moore
Maybe it’s because there’s been a lot of zombies on tv lately, with The Last Of Us, 28 Years Later, That I’ve been thinking about real life illnesses that hijack our brains and can turn us into, well, zombies. Today, I want to share with you three horrific examples that I found. And like I say with all of our morbid medicine episodes, today is a bad day to be a hypochondriac!
Before we jump in, a quick heads up we will be launching brand new Heart Starts Pounding merch in just a couple of weeks. I’ve been wearing the samples around for a few weeks now and I can’t wait to share with you guys. There will also be a special limited edition Dark Summer t-shirt because starting July 9th, we are launching our second installment of Dark summer. It may be the most relaxing time of the year but that doesn’t mean there’s not something still lurking around every corner
And of course if you’re a Patreon or Apple Podcasts subscriber you’ll get a discount on merch–so basically the subscription pays for itself. Apple subscribers, stay tuned through the end of this episode for a special message on how to get your discounts. Patrons I’ll be posting more details for you on Patreon as always. Ok, let’s get to it.
BREAK 1
So what exactly is rabies, and why is it so terrifying? Humans have known rabies exists, and is transmitted by animal bites, for thousands of years. A legal code preserved from the 23rd century BCE in Mesopotamia included a reference to people dying after being bitten by “mad dogs.”
There are two ways the disease can go. About 15-20% of cases are what’s called “paralytic rabies,” meaning the infected person or animal becomes completely unable to move before dying. The other 80-85% of cases are the very, very scary kind. They’re known as “furious rabies.”
Animals with furious rabies compulsively attack and bite anything and everything they can. They’re so enraged, nothing can stop them. People have even shot rabid animals, just to watch them get up and keep on attacking. They also produce extra saliva, which makes them appear to be “foaming at the mouth,” or sometimes just drooling.
You’ll know if you see a creature with furious rabies. Its behavior wont make any sense. Maybe it’s a coyote out in the middle of the day, walking like its limbs are locked, foam dripping from its mouth. If you see them, don’t go outside, because if they see you, they may come at you with almost unstoppable force.
When humans get furious rabies, they may become uncontrollably angry, too. People with rabies used to have to be physically restrained to keep their limbs from flying at doctors
There’s actually a video that the US Army Medical Service put out in 1955, that filmed 29 villagers from a small village in Iran who were attacked by a rabid wolf. The black and white silent video hopes to educate on the manifestation of the disease, but the results are horrifying.
In it, a man has his legs and wrists bound to the bed. His eyes gaze up at the ceiling but it doesn’t really seem like anyone is in there. A nurse wipes the foam that keeps forming around his mouth. It seems like a horrible, horrible experience, and after 5 days of getting worse, he passes away. (Video: https://www.youtube.com/watch?v=OOu2JjQmS6Y&rco=1)
But one thing that he does towards the beginning, when his mind and body aren’t totally ravaged by the disease, is he goes to take a sip of water, and then his whole body jerks and he spits it out. What he’s experiencing, is probably the strangest symptom of all of rabies. It’s something called Hydrophobia.
Hydrophobia is the fear of water. When someone with rabies drinks water, or even thinks about drinking water, it triggers painful throat spasms. So painful, apparently, that this symptom overrides all the other types of pain that go along with rabies. The only thing they can focus on is getting away from the water. (video: https://www.youtube.com/shorts/kiz3tQmB-UQ)
Hydrophobia isn’t a universal rabies symptom, though. If a rabid animal comes after you, don’t count on a bowl of water to stop it dead in its tracks. Just get away as fast as you can.
Whatever you have to do to avoid getting rabies, it’s worth it. Rabies deaths are so agonizing, and its symptoms so bizarre, many cultures historically interpreted dying victims’ contortions and howls of pain as demonic. I mean, imagine a priest throwing holy water on someone who is deathly afraid of water…. It’s going to look like there's a demon inside of the person
in some parts of Thailand to this day, monks will perform a form of exorcism on victims of rabies. If someone has been bitten by what they believe is a rabid animal, they need to play dead. The monks will then hold a mock funeral for the victim, carrying them on a funeral pyre into the town center where people pretend to weep for their death. Then, the monks will light the pyre with matches, and the victim must stay on the pyre for as long as possible as the flames grow under them. The pretend cremation is supposed to rid the body of the spirits that cause Rabies.
It wasn’t until 1804 that someone figured out that it wasn’t demons, or spirits… it was saliva. Scientist Georg Gottfried Zinke proved that he could infect a healthy animal with rabies by injecting it with the saliva of a rabid animal.
81 years later, a guy you may have heard of, Louis Pasteur—yes, the same one who came up with pasteurization for milk—created the very first rabies vaccine. He harvested the spinal cords of infected rabbits, then partially deactivated the virus through a process called “attenuation.” Basically, he dried it out almost enough to completely stop it, but not quite. Then he injected it into uninfected dogs, and their immune systems responded by creating rabies antibodies.
Pasteur wasn’t ready to offer the vaccine to humans. But then, one night, on July 6th 1885, a crying mother showed up on his Paris doorstep holding her nine-year-old son in her arms, Joseph Meister. His clothes were tattered and streaked with blood after being savagely bitten fourteen times by a neighbor’s rabid dog. Pasteur’s team agreed to vaccinate Joseph 12 times over the next 10 days, using progressively larger doses of virus. It was a dangerous experiment, but what choice did they have?
Everyone held their breath waiting for Joseph to get rabies… and nothing happened. Joseph Meister grew up healthy, and lived until 1940.
From that moment on, rabies vaccines have been available to both humans and animals. And they’ve only gotten more effective over time.
Unfortunately for Jeanna Giese, the development of vaccines didn’t lead to treatments for rabies. Doctors told Jeanna’s parents she was almost certainly going to die. Maybe even that day. By that point, she was barely conscious—she occasionally woke up enough to respond to simple commands from her doctors, but she had to be intubated to help her breathe, so she could no longer communicate.
Hospice care was one option, either at home or in the hospital. Jeanna would be given sedatives and painkillers, but they wouldn’t try to prevent her from dying. Or she could remain in intensive care—but nobody had ever survived rabies that way. Neither choice offered any real hope.
One doctor, pediatric infectious diseases specialist Rodney Willoughby Jr., suggested a third option. But it was a brand-new idea, and he was a brand-new member of the medical staff. It was only his second on-call shift at the Children’s Hospital of Wisconsin.
Dr. Willoughby theorized that rabies patients were dying mostly because their brain activity was altered by the virus, causing their brains to signal their other organs to overheat and burn themselves out. If he could stop Jeanna’s brain from sending bad signals, Dr. Willoughby believed he might be able to buy her immune system enough time to win its battle against rabies.
Dr. Willoughby told Jeanna’s parents she would probably die no matter which option they chose. But, if they requested it, he was willing to try to save her… by putting her in an induced coma.
Jeanna’s parents decided to try it. Even if Jeanna died, they thought maybe her short life would help doctors learn something that could later save other patients.
So, Dr. Willoughby anesthetized Jeanna by dosing her with ketamine and midazolam until her brain waves showed that she was in a comatose state. Essentially, she was sleeping the deepest sleep imaginable, with her brain activity suppressed as much as it possibly could be without killing her.
Then, they waited… mostly for bad news. Even if Jeanna didn’t die, there was another worst-case scenario, too: she could live, but with “locked-in syndrome.” She’d be conscious, but so completely paralyzed she could only move her eyes.
That was Dr. Willoughby’s worst fear. If she died, that would just be the expected course of the disease. But if she got locked in, it would be his fault.
To everyone’s surprise, when the anesthesia was withdrawn two weeks later, Jeanna was still alive. And she wasn’t locked in. On the 16th day after her coma was induced, Jeanna responded to human voices by raising her eyebrows and opening her mouth. By the 23rd day, she could sit up in bed, and by day 30, she cried in response to feelings of sadness. She wasn’t just moving, she was thinking and feeling.
Jeanna was like a newborn baby again in a fifteen-year-old body. She had to relearn everything: how to walk, how to talk, how to smile, how to laugh… and she had to do it all in the spotlight. As the first person ever to survive rabies without a vaccine, Jeanna became a celebrity patient overnight.
Today, Jeanna is a married mother of three who works at the Fond du Lac (lack) Children’s Museum. She still has permanent nerve damage and some trouble with her balance, but she’s functioning much, much better than anyone ever expected.
Back in 2004, when Jeanna’s survival was announced, people assumed her treatment would become the standard of care for symptomatic rabies in humans. It got a name: “The Milwaukee Protocol.” And doctors around the world were thrilled to have at least one treatment option that might give people with rabies a fighting chance.
But it wasn’t the game-changer everyone hoped for. Over the next 20 years, a few more people did survive rabies—33 in total, as of now. And that’s out of tens of thousands of cases. Some of them received the Milwaukee Protocol treatment. Others just received intensive care. Most were left severely disabled.
I will say, though, if you do happen to get bit by a bat, which is how most rabies deaths in the US start, there might be some good news in the future
In 2024, a team working with the U.S. Defense Department announced they’d developed a possible cure for rabies… in mice, anyway.
these researchers made a monoclonal antibody drug for rabies. And when they tested it in mice, they were able to cure their rabies, even after they had symptoms.
Obviously, prevention is still the priority—it’s way better to get a vaccine than a risky experimental treatment—but this new approach is promising. Maybe soon we’ll be able to say the original “zombie virus” has been cured.
STORY 2
Toxoplasma gondii
In 2019, a 14-year-old girl in rural Turkey, who we’ll refer to as Nina, noticed a few changes to her personality. First, her parents noticed that she was acting particularly moody. Ok, whatever, she’s a 14 year old girl, they didn’t really think much of that. But then she was becoming increasingly more distracted, like she was never fully there when talking to them. And then, she stopped communicating with them. Her once long answers became one word responses.
Now, none of this is all that weird for teenagers, but it was just SO unlike Nina. She would have phases where she would be moody, but this phase wasn’t passing. Actually, it was getting worse and worse, each day she was becoming more gloomy, she was speaking to them less and less. And her parents started to worry that her life might be at risk if she didn’t start feeling better soon.
So, they brought her to a therapist where Nina was diagnosed with clinical depression.
What came next were antidepressants. She was prescribed the generic form of Zoloft, sertraline. But That didn’t alleviate her symptoms at all. Next the psychiatrist tried fluoxetine, which is the generic equivalent to Prozac. But N didn’t feel any better, either, actually she felt worse.
For the next year, Nina’s depression just worsened, and then A little over a year after the onset of her symptoms, she developed strange swellings on her neck. It was her lymph nodes—they were so enlarged, the doctors thought she probably had cancer. The next step was a complex surgery to remove the diseased nodes. Nina was referred to a larger state hospital in nearby Manisa (mah-nee-sah), Turkey.
N’s new doctors decided to conduct a psychiatric evaluation before surgery. But N was so depressed, she couldn’t even pay attention to the doctors’ questions. After testing, they ranked her as “6 - severely ill,” the second-most severe category on the depression scale they were using. They ordered an increase in her fluoxetine dosage and scheduled the surgery.
Two months later, on the surgery date, Nina was still severely depressed even on the higher dose of her SSRI. Her enlarged lymph nodes were removed, biopsied, and sent off for testing.
When the results came back, the surgeons were shocked. Nina didn’t have cancer. She had something else entirely. Something that her doctors had only ever read about in medical journals.
Nina tested positive for a parasite called Toxoplasma gondii. It’s a single-celled organism called a “protozoan.” What, exactly, protozoans are is really complicated, evolutionarily speaking, but the shortest way to describe them is to explain what they’re not: they aren’t animals, plants, or fungi. Not all of them are parasites, but Toxoplasma gondii is.
It’s also pretty difficult to treat, especially once a bunch of those single cells group together to form cysts… which are often found in the patient’s brain.
Toxoplasma gondii has a trait that’s incredibly rare among parasites: it can completely change the host’s behavior, almost hijacking their brain. For instance, when rats and mice are infected, they actually become less afraid of cats. Sometimes, infected rodents actually appear to be attracted to cats.
Cats are the sneaky parasite’s favorite host. Toxoplasma gondii can only reproduce sexually when it’s infecting a feline. It can replicate non-sexually in other hosts, but sexual reproduction confers a survival advantage.
Somehow, the protozoans inside rat brains know they need to be inside a cat to reproduce… so they force their second-choice host, the rat, to get itself eaten by their first-choice host, the feline.
But, the most common way adult humans get infected is by eating undercooked meat. Especially beef and pork. In France and Brazil, where raw or partially raw beef is considered a delicacy, toxoplasmosis infections are much more common than in countries that typically cook meat thoroughly.
Research is ongoing to figure out whether or not toxoplasmosis increases risk-taking behavior in humans, like it does in rats, but some scientists think it’s possible. Several human studies have linked the parasite to schizophrenia, as well as other mental illnesses, and even a person’s likelihood of auto accidents, strangely enough.
Obviously, it’s unethical to infect humans with toxoplasmosis on purpose, and illegal to do so just to cut open their brains and look for cysts later… so it’s probably going to take a long time to figure out for certain how toxoplasmosis affects human behavior.
But one thing we do know is what happened to our young patient, Nina
The hospital wrote her a prescription for a drug called Clindamycin. Doctors hoped the medication would shrink her remaining swollen lymph nodes and keep the swelling from coming back.
And they were shocked when, at her follow-up exam, Nina not only had less swelling… she had a whole new personality. She was cheerful and happy to talk with her medical team.
After administering another psychiatric evaluation, the doctors learned N’s depression level had plummeted to a 3, or “mildly ill.” In other words, she was only about half as depressed as she’d been before.
Now, I’m not saying that if you’re depressed and love cats that you have a personality altering parasite inside of you, but I’m not saying that you don’t either.
More, after the break.
BREAK 2
In Fort Collins, Colorado, in 1967, Gene Schoonveld, a Colorado State University researcher, was studying how to help mule deer avoid starvation under harsh winter conditions. He sent a team to capture a few wild deer and bring them to CSU.
The university temporarily housed its new deer with sheep being used in other research. The animals didn’t seem to mind each other’s company, and they had similar dietary needs.
Once the deer got pens of their own, Gene separated them into a few groups and tried various methods of supplementing them through the winter.
But they just kept losing weight, no matter how much he fed them. The more they ate, the skinnier they got. Pretty soon, some of them looked like walking skeletons.
And weight loss wasn’t the only problem. Their behavior changed. They became clumsy, walking aimlessly in repeating patterns. Their eyes seemed to glaze over. Their coats became rough and matted. They lumbered stiffly across their pens, walking into each other as if they couldn’t tell who or what was in their path. Some of them started drooling.
A few even became aggressive, charging the researchers. emaciated bucks with their antlers lowered and a vacant, glassy look in their eyes. They described it Almost like being chased by a dead body.
Gene tried changing their diet, medicating them for infections, and testing them for every disease he could think of. But every test came back clean. They didn’t seem to have parasites, bacterial infections, or a virus. Their food wasn’t poisoned. The soil wasn’t contaminated.
And yet, the deer just kept starving to death, with huge piles of food right in front of them. Almost every deer captured and brought to the facility eventually got sick. From the moment they arrived at CSU, they were dead deer walking. And nobody knew why.
If he was a superstitious man, Gene might have wondered if CSU’s deer pens were cursed.
the mysterious illness and deaths were still happening 10 years later when a graduate student named Beth Williams decided to look into it. Research into the sickly deer had largely gone dormant, maybe they did just start to assume they were cursed. Gene and his colleagues had already investigated dozens of possibilities without learning anything useful.
But Beth had a new idea. She decided to take a look at the brains of some of the deer that had died of the mystery condition. What she saw was frightening: when Beth sliced off a thin piece of brain tissue and looked at it under her microscope, it was full of tiny holes. Like a sponge.
Something was literally eating away at the deer’s brains over time. But what? The brains didn’t show any signs of parasites or infection.
Beth realized she’d seen this before. The university was also researching a perplexing disease that was starting to affect sheep and goats, called “scrapie” because infected animals tended to obsessively scrape their sides against fences down to the bone. Like the sick deer, they also became uncoordinated and lost weight in the late stages of the disease. And, when necropsied after death, they also had tiny holes in their brains.
Early experiments had shown that only sheep and goats could get scrapie. Still… there was that brief period at the beginning of Gene’s deer study, when the deer were housed with sheep. Some of those sheep were part of CSU’s scrapie study. Could the disease have jumped to a new species for the first time, right on the grounds of the university?
It was just barely possible. But that didn’t give Beth a lot of hope for the deer who were infected… scrapie is 100% fatal, with no way to treat or prevent it. Even after studying multiple generations of sheep, researchers still didn’t know what caused scrapie. Just like the skinny deer, scrapie sheep seemed to get sick for absolutely no reason at all.
Beth shared her findings with others, and the condition she’d discovered was given a name: Chronic Wasting Disease. It’s often called by the nickname “zombie deer disease,” because animals in the later stages of the illness really do look like reanimated corpses.
Some people hoped CWD would just go away as the herd at CSU died off, but that didn’t happen. The deer kept getting infected, and then In 1981, CWD was confirmed in wild deer for the first time. Once it got into wild populations, it started spreading to commercial game farms and even zoos.
Animal keepers soon learned that once Chronic Wasting Disease has infected a facility, it’s impossible to decontaminate. They’d bleach the entire facility. Deer kept becoming undead. Ultraviolet radiation, same thing. Even removing and replacing the soil doesn’t work. Once the disease gets a foothold in a place, every deer ever kept there in the future will be exposed. And every deer that gets infected will slowly waste away, becoming more and more uncoordinated and corpse like until it dies. .
It took decades after Beth’s initial discovery for scientists to figure out what causes CWD, scrapies, and other similar diseases that leave holes in the victim’s brain: misshapen proteins called “prions.”
So, A lot of your bodily functions depend on proteins. For example, hugging someone you love can cause your brain to release oxytocin, a neurotransmitter associated with bonding. That chemical reaction is only possible because of special precursor proteins, which the brain processes to create oxytocin. Without proteins, you literally couldn’t feel love.
But sometimes those microscopic proteins get folded the wrong way. Instead of carrying messages that tell your brain to function correctly, misfolded proteins destroy brain cells.
Worse yet, they convince other proteins to fold themselves improperly, too. Kind of like how cancer cells convince the body to produce more cancer cells, and viruses feed on your cells to replicate themselves.
The difference is, your immune system has ways to respond to cancer and viruses. Which means we can develop drugs that help your body kill those pathogens. But the immune system just plain doesn’t recognize proteins as a threat, no matter how they’re shaped.
That means vaccines aren’t an option. And any drug we could give a person or animal to kill the prions in their body would destroy healthy proteins, too, eventually killing the patient.
Not only is it impossible to get rid of prions inside the body, they’re functionally immortal outside of it, too. There’s no way to sterilize something that’s been exposed to prions. If disease-causing prions get on a surgical tool, for instance, they’re there forever.
In other words we have no way to contain or manage prion diseases, short of killing every exposed animal. And, bad news, CWD is spreading. After first being detected in just one herd in one state, CWD is now present in 36 states and five Canadian provinces.
Which raises one big, huge question: can humans get it?
Well, in 2024, two elderly hunters from the same lodge started coming down with very strange symptoms after they ate deer from a CWD-infected area. Symptoms that mimicked CWD. Poor memory and coordination, sudden, jerky movements and trouble speaking. Both eventually died of Creutzfeldt-Jakob’s Disease, a human prion disease. CJD isn’t the same thing as CWD, but it is what CWD would theoretically cause in humans if it ever crossed the species barrier.
When the news broke about the hunters, people started panicking. It was on every news site, there were countless youtube videos. Hunters were terrified. This was their worst-case scenario. A 100% fatal disease, with no test, treatment, or cure, spreading like wildfire among deer and elk. Some people swore off eating venison entirely.
They wanted to know, what was their risk of getting this? Could you or I start wasting away and losing our minds from this deer disease?
But… it turned out that was probably a huge overreaction. Creutzfeldt-Jakob’s Disease can occur spontaneously in humans. Mostly in people over 60 years old, which both hunters were. There wasn’t even any proof that either of the hunters ate a deer infected with CWD. They’d just hunted in areas where the disease is common.
So, great news, humans probably still can’t get CWD… although you probably still shouldn’t eat a sick deer’s brain.
However, even though you might be safe from CWD, I can’t tell you not to worry about prions at all. Because there is one known prion disease that humans can get from animals: Bovine Spongiform Encephalopathy, aka Mad Cow Disease. During an outbreak in the United Kingdom in the 1980s and 1990s, thousands of British beef consumers were potentially exposed. Since then, at least 232 people have died as a direct result of eating infected beef.
There will be more deaths, even if nobody ever eats a mad cow again. Scientists believe some people still have prions from the outbreak incubating in their bodies, which will eventually turn into CJD. There’s no way to predict when. But, once they do get sick, they’ll all die.
I set out to make this episode to try and make myself feel better about these illnesses. There’s no way you or I could ever come down with any of these, right? But then I really thought about it. If there ever were someone to own a cat, to frolick in the forest amongst the deer, and to not be afraid to venture into a dark bat cave….it’s definitely one of us here in the Rogue Detecting society. That’s all the things WE like to do!!
What do you guys think, have you ever known anyone who has come into contact with any of these illnesses? Please let me know wherever you listen, and be sure to rate, review and subscribe to the show, all of that engagement really helps a show like this, and your support is everything.
That’s all I have for you today though. Go pet your cats for me, I’m sure you’ll be fine, and meet me here next week…
Until next time, Stay parasite free and stay curious.