8 ms·

Rage Disorder Linked with Toxoplasmosis (2016)

223 points by stephengillie 9y ago

lima 9y ago
Toxoplasmosis is an extremely interesting parasite. I wouldn't be surprised if it is recognized as an important public health issue in the coming decade. Is has been linked to all sorts of disorders, including schizophrenia and bipolar disorder. Prof. Jaroslav Flegr contributed many important studies, especially in the early stages of toxoplasmosis research [1]. He was also featured by an Atlantic article, which was one of the first to bring public attention to the field of research [2]. One particularly interesting finding is how it interacts with the RH factor. It might explain the relative stability of the distribution of the two types in the population even though one of them should have a serious disadvantage (birth complications) [3]. The hard question is how to prevent it. Due to how many different infection vectors there are, the only sound pieces of advice are "eat your meat well done" and "avoid getting in contact with garden soil". Development of a vaccine for cats is a promising solution since the parasite can only be transmitted by cats. [1]: https://web.natur.cuni.cz/flegr/publ.php https://web.natur.cuni.cz/flegr/publ.php [2]: https://www.theatlantic.com/magazine/archive/2012/03/how-your-cat-is-making-you-crazy/308873/ https://www.theatlantic.com/magazine/archive/2012/03/how-you... [3]: https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf
- sillysaurus3 9y ago
  After learning about the perverse incentives for publishing scientific papers, I find it extremely difficult to trust new research. Any tips for reversing this mindset? I know it's not too great to be feeling this way. Scientists have immense incentives for publishing new results. As someone quipped, "there is no cost in getting something wrong; the cost is not being published." Toxoplasmosis in particular seems intuitively like the perfect combination of new research plus massive prestige for whoever publishes papers on the topic. And we can't trust articles written on the topic either; they do little more than parrot whatever the scientists say, and don't really cast a critical eye on the methodology or findings. Which makes sense. I mean, how could they? None of us are experts the way a scientist is an expert. But it used to be a hobby of mine to dig through research papers and find subtle inconsistencies. Take fatal familial insomnia, for example. It's not fatal due to the insomnia. That's a misnomer. But the fact that it wasn't related to the insomnia was buried on the 7th page of the report as basically a footnote. I don't know. I just wish it were easier to take a lot of this at face value.
  - theprotocol 9y ago
    I share your concerns, yet can't think of a solution. I think the only thing that can be done is to factor in a large amount of doubt, and amortize that doubt as more definitive studies come in over time.
  - autokad 9y ago
    the biggest problem is the reliance on linear models and their interpretations. its easy to have something statistically significant but yet produce a shitty prediction. they then take this horrible model and use its coefficients to make ridiculous claims, like doing X makes you Y times more likely to Z. thats great for a business wanting to find ways to make money, but when this crap gets in the government level these crappy models are used to legislate us.
  - bogomipz 9y ago
    >"After learning about the perverse incentives for publishing scientific papers ..." Can you be more specific, what was the source or your learning? Was there a particular piece or pieces you read? If so would you be able to share them?
  - DanBC 9y ago
    > I find it extremely difficult to trust new research. Any tips for reversing this mindset? I know it's not too great to be feeling this way. Why is it not great to feel this way? You give a bunch of good reasons why it is okay to feel as you do. In general you should ignore any new research until it's had a large well run meta-analysis of it. Until then, it's all "we think" and "maybe". And that's ok, unless you're forcing people to take a treatment or depriving them of their liberty based on the research.
  - epistasis 9y ago
    >Toxoplasmosis in particular seems intuitively like the perfect combination of new research plus massive prestige for whoever publishes papers on the topic Eh, not really much prestige, but perhaps lots of press. The big thing is to not take any single paper as "scientific truth" like what you read in a textbook. The scientific literature is not a textbook, it's the place where science's self-correction happens. Things in text books have been battle-tested, and widely accepted usually due to replication. And even then, textbooks have errors and perpetuate some falsehoods! Any individual scientific paper will not even likely be replicated, because it's working on something that did not turn out to be fundamental to the path of science. Scientific papers in the literature are how scientists share their small steps while exploring the n-dimensional world. That n is very high, so there are lots of directions to explore, and most of them will not be that interesting. If it is, somebody else may decide to take a look too. If it's a hot-topic, then many many people will. Scientists have to operate in a world where they are exploring what is and is not true, and their relationship with uncertainty is strong; it's absolutely essential to embrace uncertainty. The biggest thing is to distrust news reporting about science. It's correct about 1% of the time. The motivations of a reporter trying to somehow make an interesting article by deadline on a topic they don't understand are far more distorted than the scientists publishing a paper they expect 30-50 people to ever read. And that's if you actually get a real reporter to look at these things; most articles are just press releases that are cut and pasted from a university press lackey into the newspaper's publishing system. Those are usually even worse.
- tr1ck5t3r 9y ago
  Its a biological weapon thats been in used since Ancient Egyptian times considering their worshiping of cats. One of thing, freeze your meat, and whilst theres very few reliable tests, most people can self diagnose by looking for floaters in their vision. In males in causes and increase in testsotorone and thus dominant aggressive risk taking behaviour, in women it causes the opposite, shy, timid, risk averse behaviour. In a way, its probably got its own survival strategy sorted when looking at the procreation habits of its hosts, but so little is known.
averagewall 9y ago
This is the same parasite that supposedly causes mice to become permanently unafraid of cats and attracted to cat urine.
- slig 9y ago
  There are videos showing mice going after cats and the cats know instinctively that there's something very wrong and they run away.
  - bogomipz 9y ago
    Do you have a link?
    - slig 9y ago
      This is not the video I had in mind, but here it is https://youtu.be/XQ4Y27RQaZk https://youtu.be/XQ4Y27RQaZk
  - knodi123 9y ago
    > cats know instinctively that there's something very wrong and they run away But why? Most cats who catch it are asymptomatic....
antidaily 9y ago
So I had a thing with this as a young kid. It caused burn-like scars on my retina. No symptoms after that or vision changes. Did it alter my brain? I don't think so. I will rage in my car when someone is in the left lane driving slow.
- eritain 9y ago
  There is so much visual processing machinery in the retina that some neuroscientists describe it as an outpost of the visual cortex. In that sense, scarring your retina might indeed have altered your brain. But not in a way that's related to emotional control.
  - jpfed 9y ago
    Your eyes are also an outgrowth of the neural tube.
jhanschoo 9y ago
Note that toxoplasmosis is extremely common and is sufficiently benign for most people that it does not really warrant worry or concern from the general populace. There are more important and actionable factors affecting most of us.
- tartuffe78 9y ago
  Said the parasite!
- wahern 9y ago
  Yeah. I'm as fascinated by the theory as the next geek, but the evidence for a causal connection has remained pretty thin for awhile. The case for lithium in ground water reducing incidence of depression and suicide seems stronger. So if one is worried about toxoplasmosis then maybe they should also be buying pallets of Pellegrino, as it's the most widely available bottled water with the highest concentration[1] of lithium. It's part of how I justify the expense to my spouse :) [1] It's still only a small amount. You can actually buy lithium water on Amazon with orders of magnitude more lithium, but that seems unwise....
- relyio 9y ago
  Well, we don't know that. It hasn't been studied. See: https://en.wikipedia.org/wiki/Lead_and_crime_hypothesis https://en.wikipedia.org/wiki/Lead_and_crime_hypothesis.
Pigo 9y ago
Joe Rogan has talked about this at length on his show several times, and had Robert Sapolsky as a guest to talk about this. They actually say the parasite causes rats to become sexually attracted to cats, causing them to pass on to the cat once it's inevitably killed. Life sure does find a way. https://www.youtube.com/watch?v=NroiGfNohPo https://www.youtube.com/watch?v=NroiGfNohPo
- rsync 9y ago
  This is why I am skeptical/cautious about the "let's just kill all the mosquitos" plans I see floated ... Even if it's true that mosquitos can be removed from the foodchain with no negative effects ... are we so sure that wherever malaria goes (and I think it will go somewhere) won't be worse than mosquitos ?
  - yaacov 9y ago
    If malaria had some other way to spread it wouldn't wait until mosquitos were wiped out to use it. It's not like the parasite is intelligent or anything.
  - _jal 9y ago
    I don't worry about malaria per se; as another poster noted, if it had a different vector, we'd see it already. I do worry about removing critters from the food chain; we've seen plenty of second- and third-order surprises from that. What do the things that eat mosquitos find next-most-tasty, for starters?
- nealabq 9y ago
  If you're starting a family, consider these words from Robert Sapolsky: "The parasite my lab is beginning to focus on is one in the world of mammals, where parasites are changing mammalian behavior. It's got to do with this parasite, this protozoan called Toxoplasma. If you're ever pregnant, if you're ever around anyone who's pregnant, you know you immediately get skittish about cat feces, cat bedding, cat everything, because it could carry Toxo. And you do not want to get Toxoplasma into a fetal nervous system. It's a disaster." "There's a long-standing literature that absolutely shows there's a statistical link between Toxo infection and schizophrenia. It's not a big link, but it's solidly there. Schizophrenics have higher than expected rates of having been infected with Toxo, and not particularly the case for other related parasites. Links between schizophrenia and mothers who had house cats during pregnancy." https://www.edge.org/conversation/robert_sapolsky-toxo https://www.edge.org/conversation/robert_sapolsky-toxo
phkahler 9y ago
They say about 20 percent of the US population has been infected and then we see this: The research team found that 22 percent of the people with IED tested positive for toxoplasmosis exposure, compared with only 9 percent of the healthy control group. About 16 percent of the group with other psychiatric disorders tested positive for toxoplasmosis, too. So the people with IED had about the same rate of infection as the general population. This looks to me like one of those "nothing to see here" situations based on the numbers.
- AnimalMuppet 9y ago
  Maybe not. That 9% number for the control group stands out. That number and the 20% number for the population as a whole seem to me to be incompatible - or, perhaps, measured in different ways. If the 9% healthy and 22% with IED are both accurate (and the 20% number is the one that's off), then there may in fact be something to see here.
- averagewall 9y ago
  Perhaps healthy means younger than the general population and younger means less chance of having been infected yet. Those 20 percent of the population infected might be skewed towards old people.
woliveirajr 9y ago
The treatment for Toxo isn`t a easy one: when thing get serious you take massive doses of pyrimethamine and sulfadizine, for example, and have to take extra folinic acid (not folic, folinic). And it won't kill all T. Gondii, it will remain latent inside your body. There were some studied, few years ago, about combining pyrimethamine and aminoacids to kill the latent toxo, but I didn't find the results, if it even worked or not. For almost everybody, infection will go away without signs. For few others, it will make you remember it for the rest of your life.
- ajmurmann 9y ago
  Thank you for this explanation! I listened to a long radio special about behavior assuring parasites a long time ago. Toxoplasma Gondii played a big role in the report and ever since I've been dumbfounded why we don't treat it. Even though it doesn't seem to have a negative immediate health benefit behavior alteration especially towards higher risk taking is terrifying to me. Thanks to your explanation of the cost of treatment this makes more sense.
fnord123 9y ago
This is consistent with research linking Toxoplasmosis with PMDD [0] [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/
oldsklgdfth 9y ago
Robert Sapolsky, a neuroscientist, talking about toxoplasmosis. https://www.youtube.com/watch?v=m3x3TMdkGdQ https://www.youtube.com/watch?v=m3x3TMdkGdQ He touches on some very interesting observations that have been made about the infection and behavior.
prepaciously 9y ago
It makes one wonder how healthy those home-grown salad vegetables might really be, given that a garden plot makes a convenient litter tray for roaming felines.
- planteen 9y ago
  What makes you think commercial fruits & vegetables are any different? Nearly every farm has tons of feral cats around.
  - prepaciously 9y ago
    I must admit I didn't know about the feral cats wandering around farms. But I do imagine that farmers wash their produce more consistently than home growers do, and that feline density is higher in the suburbs.
- PeterisP 9y ago
  Some buddies work in a lab doing all kinds of product (mostly but not exclusively food) analysis for chemical and biological contamination, pesticide levels, etc; and they also do some research and run the same tests on all kinds of stuff they find personally interesting, including things they would personally consume. Their experience is that the general commercial products are the safest to use - all the organic small scale farmed stuff sold to the general public is highly hit and miss, sometimes they're less contaminated but quite often it's literally off the charts e.g. hundredfold exceeding the limits allowed for commercial products, or have all kinds of dangerous bacteria (indicating e.g. fecal contamination) that they've never seen in samples of the mass produced food. Also, things their relatives have grown not for sale but for themselves with the purest intent have sometimes been contaminated - e.g. some parasites in their pork. TL;DR - home-grown stuff can be expected to be less healthy and more dangerous than the industrial farming processes in well regulated first world countries. Often more tasty, though.
Dowwie 9y ago
I can see attorneys using this as a defense going forward
- nerpderp83 9y ago
  Honorable Members of the Jury, you can clearly see that my client couldn't possibly be responsible for his actions, as he just ingested a Twinkie with a Soft Nougatie Cat Feces Filling!
ggm 9y ago
reversible? or permanent brain function change?
- deleted 9y ago
  [deleted]
HillaryBriss 9y ago
> It correlates also with diseases burden associated with bipolar disorder, obsessive compulsive disorder, and epilepsy though the headline does not emphasize it, there's an OCD correlation too.
ajmarcic 9y ago
Toxoplasmosis is naturally contracted from cat exposure and care. Anecdotally I see mentally ill people as being drawn to cat ownership for their personal comfort and fascination. https://en.wikipedia.org/wiki/Louis_Wain https://en.wikipedia.org/wiki/Louis_Wain It is a difficult leap to go from saying "people with certain mental illnesses own cats, and thus are likely to have TP" to "TP causes mental illness". If we are to believe cat owners are more likely to have mental illness, a correlation of mental illness and TP serum positivity follows naturally.
- nerpderp83 9y ago
  Are you saying people with mental illness seek comfort via pets (cats). Shouldn't we see an affinity for other social pets besides cats?
  - shubb 9y ago
    You could probably answer this question using this resource [1]. However, someone used it to show no associations between psychotic episodes (specifically) AFTER controlling for other factors (that are associated with cat ownership)[2]. Using the adjustments they made, I could wildly speculate that possibly dog owners will be less likely than cat owners to have mental illness, because dogs require a certain amount of wealth, living space, etc - and the lack of these things is associated both with cat ownership and mental illness, maybe, just not in rural areas... [1]http://www.bristol.ac.uk/alspac/researchers/access/ http://www.bristol.ac.uk/alspac/researchers/access/ [2]https://www.cambridge.org/core/journals/psychological-medicine/article/curiosity-killed-the-cat-no-evidence-of-an-association-between-cat-ownership-and-psychotic-symptoms-at-ages-13-and-18-years-in-a-uk-general-population-cohort/75C9A48B669BE36E947AFB0BC5CB00CA/core-reader https://www.cambridge.org/core/journals/psychological-medici...
FranOntanaya 9y ago
I imagine people that grow up around stray cats are likely to have a different upbringing to people that don't.
- codingdave 9y ago
  That statement is a tautology. What exactly are you trying to imply by it, though?
  - racer-v 9y ago
    I imagine GP is suggesting correlation as opposed to causation.
- muzfuz 9y ago
  This very much depends on where you grow up. Plenty of countries in the world where you can live a comfortable middle class life and still be around a lot of stray cats.
Ovah 9y ago
Years ago I attended a lecture on Toxoplasmosis gondii. Intriguing (unattributed) points made by the scientist: 1) there's a higher prevalance of infection in car crash victims than control 2) by hijacking dendritic cells (blood immune cell), the parasite is able to bypass the blood brain barrier (highly protective filter of brain) 3) once in the brain, it may form cysts that may lay dormat 4) a significant portion of the world population is infected 5) if have cats weren't allowed as pets, there would hardly be any T. gondii infections
theyregreat 9y ago
If it makes rats sexually attracted to cats, it may not be such a trivial disease.

223 points by stephengillie 9y ago

lima 9y ago

Toxoplasmosis is an extremely interesting parasite. I wouldn't be surprised if it is recognized as an important public health issue in the coming decade. Is has been linked to all sorts of disorders, including schizophrenia and bipolar disorder. Prof. Jaroslav Flegr contributed many important studies, especially in the early stages of toxoplasmosis research [1]. He was also featured by an Atlantic article, which was one of the first to bring public attention to the field of research [2]. One particularly interesting finding is how it interacts with the RH factor. It might explain the relative stability of the distribution of the two types in the population even though one of them should have a serious disadvantage (birth complications) [3]. The hard question is how to prevent it. Due to how many different infection vectors there are, the only sound pieces of advice are "eat your meat well done" and "avoid getting in contact with garden soil". Development of a vaccine for cats is a promising solution since the parasite can only be transmitted by cats. [1]: https://web.natur.cuni.cz/flegr/publ.php https://web.natur.cuni.cz/flegr/publ.php [2]: https://www.theatlantic.com/magazine/archive/2012/03/how-your-cat-is-making-you-crazy/308873/ https://www.theatlantic.com/magazine/archive/2012/03/how-you... [3]: https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf

sillysaurus3 9y ago
After learning about the perverse incentives for publishing scientific papers, I find it extremely difficult to trust new research. Any tips for reversing this mindset? I know it's not too great to be feeling this way. Scientists have immense incentives for publishing new results. As someone quipped, "there is no cost in getting something wrong; the cost is not being published." Toxoplasmosis in particular seems intuitively like the perfect combination of new research plus massive prestige for whoever publishes papers on the topic. And we can't trust articles written on the topic either; they do little more than parrot whatever the scientists say, and don't really cast a critical eye on the methodology or findings. Which makes sense. I mean, how could they? None of us are experts the way a scientist is an expert. But it used to be a hobby of mine to dig through research papers and find subtle inconsistencies. Take fatal familial insomnia, for example. It's not fatal due to the insomnia. That's a misnomer. But the fact that it wasn't related to the insomnia was buried on the 7th page of the report as basically a footnote. I don't know. I just wish it were easier to take a lot of this at face value.
- theprotocol 9y ago
  I share your concerns, yet can't think of a solution. I think the only thing that can be done is to factor in a large amount of doubt, and amortize that doubt as more definitive studies come in over time.
- autokad 9y ago
  the biggest problem is the reliance on linear models and their interpretations. its easy to have something statistically significant but yet produce a shitty prediction. they then take this horrible model and use its coefficients to make ridiculous claims, like doing X makes you Y times more likely to Z. thats great for a business wanting to find ways to make money, but when this crap gets in the government level these crappy models are used to legislate us.
- bogomipz 9y ago
  >"After learning about the perverse incentives for publishing scientific papers ..." Can you be more specific, what was the source or your learning? Was there a particular piece or pieces you read? If so would you be able to share them?
- DanBC 9y ago
  > I find it extremely difficult to trust new research. Any tips for reversing this mindset? I know it's not too great to be feeling this way. Why is it not great to feel this way? You give a bunch of good reasons why it is okay to feel as you do. In general you should ignore any new research until it's had a large well run meta-analysis of it. Until then, it's all "we think" and "maybe". And that's ok, unless you're forcing people to take a treatment or depriving them of their liberty based on the research.
- epistasis 9y ago
  >Toxoplasmosis in particular seems intuitively like the perfect combination of new research plus massive prestige for whoever publishes papers on the topic Eh, not really much prestige, but perhaps lots of press. The big thing is to not take any single paper as "scientific truth" like what you read in a textbook. The scientific literature is not a textbook, it's the place where science's self-correction happens. Things in text books have been battle-tested, and widely accepted usually due to replication. And even then, textbooks have errors and perpetuate some falsehoods! Any individual scientific paper will not even likely be replicated, because it's working on something that did not turn out to be fundamental to the path of science. Scientific papers in the literature are how scientists share their small steps while exploring the n-dimensional world. That n is very high, so there are lots of directions to explore, and most of them will not be that interesting. If it is, somebody else may decide to take a look too. If it's a hot-topic, then many many people will. Scientists have to operate in a world where they are exploring what is and is not true, and their relationship with uncertainty is strong; it's absolutely essential to embrace uncertainty. The biggest thing is to distrust news reporting about science. It's correct about 1% of the time. The motivations of a reporter trying to somehow make an interesting article by deadline on a topic they don't understand are far more distorted than the scientists publishing a paper they expect 30-50 people to ever read. And that's if you actually get a real reporter to look at these things; most articles are just press releases that are cut and pasted from a university press lackey into the newspaper's publishing system. Those are usually even worse.
tr1ck5t3r 9y ago
Its a biological weapon thats been in used since Ancient Egyptian times considering their worshiping of cats. One of thing, freeze your meat, and whilst theres very few reliable tests, most people can self diagnose by looking for floaters in their vision. In males in causes and increase in testsotorone and thus dominant aggressive risk taking behaviour, in women it causes the opposite, shy, timid, risk averse behaviour. In a way, its probably got its own survival strategy sorted when looking at the procreation habits of its hosts, but so little is known.

averagewall 9y ago

This is the same parasite that supposedly causes mice to become permanently unafraid of cats and attracted to cat urine.

slig 9y ago
There are videos showing mice going after cats and the cats know instinctively that there's something very wrong and they run away.
- bogomipz 9y ago
  Do you have a link?
  - slig 9y ago
    This is not the video I had in mind, but here it is https://youtu.be/XQ4Y27RQaZk https://youtu.be/XQ4Y27RQaZk
- knodi123 9y ago
  > cats know instinctively that there's something very wrong and they run away But why? Most cats who catch it are asymptomatic....

antidaily 9y ago

So I had a thing with this as a young kid. It caused burn-like scars on my retina. No symptoms after that or vision changes. Did it alter my brain? I don't think so. I will rage in my car when someone is in the left lane driving slow.

eritain 9y ago
There is so much visual processing machinery in the retina that some neuroscientists describe it as an outpost of the visual cortex. In that sense, scarring your retina might indeed have altered your brain. But not in a way that's related to emotional control.
- jpfed 9y ago
  Your eyes are also an outgrowth of the neural tube.

jhanschoo 9y ago

Note that toxoplasmosis is extremely common and is sufficiently benign for most people that it does not really warrant worry or concern from the general populace. There are more important and actionable factors affecting most of us.

tartuffe78 9y ago
Said the parasite!
wahern 9y ago
Yeah. I'm as fascinated by the theory as the next geek, but the evidence for a causal connection has remained pretty thin for awhile. The case for lithium in ground water reducing incidence of depression and suicide seems stronger. So if one is worried about toxoplasmosis then maybe they should also be buying pallets of Pellegrino, as it's the most widely available bottled water with the highest concentration[1] of lithium. It's part of how I justify the expense to my spouse :) [1] It's still only a small amount. You can actually buy lithium water on Amazon with orders of magnitude more lithium, but that seems unwise....
relyio 9y ago
Well, we don't know that. It hasn't been studied. See: https://en.wikipedia.org/wiki/Lead_and_crime_hypothesis https://en.wikipedia.org/wiki/Lead_and_crime_hypothesis.

Pigo 9y ago

Joe Rogan has talked about this at length on his show several times, and had Robert Sapolsky as a guest to talk about this. They actually say the parasite causes rats to become sexually attracted to cats, causing them to pass on to the cat once it's inevitably killed. Life sure does find a way. https://www.youtube.com/watch?v=NroiGfNohPo https://www.youtube.com/watch?v=NroiGfNohPo

rsync 9y ago
This is why I am skeptical/cautious about the "let's just kill all the mosquitos" plans I see floated ... Even if it's true that mosquitos can be removed from the foodchain with no negative effects ... are we so sure that wherever malaria goes (and I think it will go somewhere) won't be worse than mosquitos ?
- yaacov 9y ago
  If malaria had some other way to spread it wouldn't wait until mosquitos were wiped out to use it. It's not like the parasite is intelligent or anything.
- _jal 9y ago
  I don't worry about malaria per se; as another poster noted, if it had a different vector, we'd see it already. I do worry about removing critters from the food chain; we've seen plenty of second- and third-order surprises from that. What do the things that eat mosquitos find next-most-tasty, for starters?
nealabq 9y ago
If you're starting a family, consider these words from Robert Sapolsky: "The parasite my lab is beginning to focus on is one in the world of mammals, where parasites are changing mammalian behavior. It's got to do with this parasite, this protozoan called Toxoplasma. If you're ever pregnant, if you're ever around anyone who's pregnant, you know you immediately get skittish about cat feces, cat bedding, cat everything, because it could carry Toxo. And you do not want to get Toxoplasma into a fetal nervous system. It's a disaster." "There's a long-standing literature that absolutely shows there's a statistical link between Toxo infection and schizophrenia. It's not a big link, but it's solidly there. Schizophrenics have higher than expected rates of having been infected with Toxo, and not particularly the case for other related parasites. Links between schizophrenia and mothers who had house cats during pregnancy." https://www.edge.org/conversation/robert_sapolsky-toxo https://www.edge.org/conversation/robert_sapolsky-toxo

phkahler 9y ago

They say about 20 percent of the US population has been infected and then we see this: The research team found that 22 percent of the people with IED tested positive for toxoplasmosis exposure, compared with only 9 percent of the healthy control group. About 16 percent of the group with other psychiatric disorders tested positive for toxoplasmosis, too. So the people with IED had about the same rate of infection as the general population. This looks to me like one of those "nothing to see here" situations based on the numbers.

AnimalMuppet 9y ago
Maybe not. That 9% number for the control group stands out. That number and the 20% number for the population as a whole seem to me to be incompatible - or, perhaps, measured in different ways. If the 9% healthy and 22% with IED are both accurate (and the 20% number is the one that's off), then there may in fact be something to see here.
averagewall 9y ago
Perhaps healthy means younger than the general population and younger means less chance of having been infected yet. Those 20 percent of the population infected might be skewed towards old people.

woliveirajr 9y ago

The treatment for Toxo isn`t a easy one: when thing get serious you take massive doses of pyrimethamine and sulfadizine, for example, and have to take extra folinic acid (not folic, folinic). And it won't kill all T. Gondii, it will remain latent inside your body. There were some studied, few years ago, about combining pyrimethamine and aminoacids to kill the latent toxo, but I didn't find the results, if it even worked or not. For almost everybody, infection will go away without signs. For few others, it will make you remember it for the rest of your life.

ajmurmann 9y ago
Thank you for this explanation! I listened to a long radio special about behavior assuring parasites a long time ago. Toxoplasma Gondii played a big role in the report and ever since I've been dumbfounded why we don't treat it. Even though it doesn't seem to have a negative immediate health benefit behavior alteration especially towards higher risk taking is terrifying to me. Thanks to your explanation of the cost of treatment this makes more sense.

fnord123 9y ago

This is consistent with research linking Toxoplasmosis with PMDD [0] [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/

oldsklgdfth 9y ago

Robert Sapolsky, a neuroscientist, talking about toxoplasmosis. https://www.youtube.com/watch?v=m3x3TMdkGdQ https://www.youtube.com/watch?v=m3x3TMdkGdQ He touches on some very interesting observations that have been made about the infection and behavior.

prepaciously 9y ago

It makes one wonder how healthy those home-grown salad vegetables might really be, given that a garden plot makes a convenient litter tray for roaming felines.

planteen 9y ago
What makes you think commercial fruits & vegetables are any different? Nearly every farm has tons of feral cats around.
- prepaciously 9y ago
  I must admit I didn't know about the feral cats wandering around farms. But I do imagine that farmers wash their produce more consistently than home growers do, and that feline density is higher in the suburbs.
PeterisP 9y ago
Some buddies work in a lab doing all kinds of product (mostly but not exclusively food) analysis for chemical and biological contamination, pesticide levels, etc; and they also do some research and run the same tests on all kinds of stuff they find personally interesting, including things they would personally consume. Their experience is that the general commercial products are the safest to use - all the organic small scale farmed stuff sold to the general public is highly hit and miss, sometimes they're less contaminated but quite often it's literally off the charts e.g. hundredfold exceeding the limits allowed for commercial products, or have all kinds of dangerous bacteria (indicating e.g. fecal contamination) that they've never seen in samples of the mass produced food. Also, things their relatives have grown not for sale but for themselves with the purest intent have sometimes been contaminated - e.g. some parasites in their pork. TL;DR - home-grown stuff can be expected to be less healthy and more dangerous than the industrial farming processes in well regulated first world countries. Often more tasty, though.

Dowwie 9y ago

I can see attorneys using this as a defense going forward

nerpderp83 9y ago
Honorable Members of the Jury, you can clearly see that my client couldn't possibly be responsible for his actions, as he just ingested a Twinkie with a Soft Nougatie Cat Feces Filling!

ggm 9y ago

reversible? or permanent brain function change?

deleted 9y ago
[deleted]

HillaryBriss 9y ago

> It correlates also with diseases burden associated with bipolar disorder, obsessive compulsive disorder, and epilepsy though the headline does not emphasize it, there's an OCD correlation too.

ajmarcic 9y ago

Toxoplasmosis is naturally contracted from cat exposure and care. Anecdotally I see mentally ill people as being drawn to cat ownership for their personal comfort and fascination. https://en.wikipedia.org/wiki/Louis_Wain https://en.wikipedia.org/wiki/Louis_Wain It is a difficult leap to go from saying "people with certain mental illnesses own cats, and thus are likely to have TP" to "TP causes mental illness". If we are to believe cat owners are more likely to have mental illness, a correlation of mental illness and TP serum positivity follows naturally.

nerpderp83 9y ago
Are you saying people with mental illness seek comfort via pets (cats). Shouldn't we see an affinity for other social pets besides cats?
- shubb 9y ago
  You could probably answer this question using this resource [1]. However, someone used it to show no associations between psychotic episodes (specifically) AFTER controlling for other factors (that are associated with cat ownership)[2]. Using the adjustments they made, I could wildly speculate that possibly dog owners will be less likely than cat owners to have mental illness, because dogs require a certain amount of wealth, living space, etc - and the lack of these things is associated both with cat ownership and mental illness, maybe, just not in rural areas... [1]http://www.bristol.ac.uk/alspac/researchers/access/ http://www.bristol.ac.uk/alspac/researchers/access/ [2]https://www.cambridge.org/core/journals/psychological-medicine/article/curiosity-killed-the-cat-no-evidence-of-an-association-between-cat-ownership-and-psychotic-symptoms-at-ages-13-and-18-years-in-a-uk-general-population-cohort/75C9A48B669BE36E947AFB0BC5CB00CA/core-reader https://www.cambridge.org/core/journals/psychological-medici...

FranOntanaya 9y ago

I imagine people that grow up around stray cats are likely to have a different upbringing to people that don't.

codingdave 9y ago
That statement is a tautology. What exactly are you trying to imply by it, though?
- racer-v 9y ago
  I imagine GP is suggesting correlation as opposed to causation.
muzfuz 9y ago
This very much depends on where you grow up. Plenty of countries in the world where you can live a comfortable middle class life and still be around a lot of stray cats.

Ovah 9y ago

Years ago I attended a lecture on Toxoplasmosis gondii. Intriguing (unattributed) points made by the scientist: 1) there's a higher prevalance of infection in car crash victims than control 2) by hijacking dendritic cells (blood immune cell), the parasite is able to bypass the blood brain barrier (highly protective filter of brain) 3) once in the brain, it may form cysts that may lay dormat 4) a significant portion of the world population is infected 5) if have cats weren't allowed as pets, there would hardly be any T. gondii infections

theyregreat 9y ago

If it makes rats sexually attracted to cats, it may not be such a trivial disease.