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I'd read this with some interest, but if this citation in the introduction is correct then it's not a small deal.

"Toxoplasma gondii, the parasitic protozoon of cats, infects about one-third of the human population in both developed and developing countries (Tenter et al., 2000)."

CDC puts it at over 40 million in the USA, so over 10%. https://www.cdc.gov/parasites/toxoplasmosis/index.html

Edit: here's that paper from Tenter et al. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109627/#__ffn_...

As a consequence, no two tests produce the same results in all cases, even when carried out in the same laboratory [45–54]. In addition, prevalence rates vary over time and with the age of the individuals included in the study [55–68].

The strongest thing they were willing to say is that it's higher in Latin America and west Africa, and lower in colder climates. Here's a direct link to Table 3 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109627/table/T...

I'm wondering if they controlled for cat ownership (as a likely source of infection), or if any of the variation can be attributed to the types of people who own cats.
ive heard that many get it from eating or working with contaminated food
It's the entire reason people want to study Toxoplasmosis. If it affects anything, that's going to mean a lot of people.
A couple important notes about toxoplasmosis (someone please correct me if I'm wrong, this is gleaned from Wikipedia and the CDC website):

- Cats only get toxoplasmosis from prey, and it only sticks around in the cat for a few weeks, so if you have an indoor-only cat that never goes outside and you don't have any pests, you're probably fine

- Even if your cat does go outside, the parasite doesn't become infectious until 1 to 5 days after it is shed in a cat’s feces, so if you're cleaning the litter box daily, you're probably fine as well

Where I live, streets are littered with stray cats and their feces. Every owner says they are "responsible" but numbers speak otherwise!
Wait, so if it sticks around in the cat for just a few weeks, is that also true for humans? Or is it permanent for us, and cats are just better at getting rid of it?
I'm not sure. That's based on this excerpt from Wikipedia[0]:

> Cats excrete the pathogen in their feces for a number of weeks after contracting the disease, generally by eating an infected intermediate host that could include mammals (like rodents) or birds. Oocyst shedding usually starts from the third day after ingestion of infected intermediate hosts, and may continue for weeks. The oocysts are not infective when excreted. After about a day, the oocyst undergoes a process called sporulation and becomes potentially pathogenic.

I guess I was not quite correct -- it may be that it sticks around longer in the cat, but it is only excreted for a few weeks.

0: https://en.wikipedia.org/wiki/Toxoplasmosis#Transmission

If it's true that toxoplasmosis is is present in 1/3 - 1/2 of the population, I immediately find any specific findings like this dubious since the scale of confounding factors must be enormous. Yes, they controlled for some, like malnutrition, but that's hardly the whole story.

It's way more likely that there is something else (maybe many other things!) that explain the correlation.

It's one of those sexy findings that is probably bullshit.

I don't follow; doesn't a larger affected population make it easier to control for confounds?
If you identify them.
I still don't follow. You don't have to control for each confounding variable if you select your pool at random, like they did here.
Getting a random pool works when your size (n) is not so many magnitudeblevels below of totalvpopulation (N). For example, say we are about to measure X variable on a deer population of 10k. If we capture 100 dears, we are good. Of we get less, maybe too. But with humans, the population is huge. This doesnt mean its impossible.
> It's one of those sexy findings that is probably bullshit.

Yeah and also one that gets highly upvoted on the sites of people who think a certain way. Social media really has contributed to clickbait confirmation bias brainrot.

Yeah but even if it's not a causal relationship it's incredibly suggestive. It mirrors my own personal experience and what I've seen in others. I'm pretty much a bleeding heart liberal now but I used to be super conservative to the point where my friends had to sit me down and have an intervention. It matches exactly with the time in my life when I was in constant stress, horrible mental health, even worse physical health. It really was, "I'm incredibly lonely and isolated, people suck and treat me like shit, I hate myself, and I have no support why should anyone else get it?" Like damn, I never connected the dots.

It took so long to turn my life around that I never even noticed the shift. It's so obvious in hindsight jesus.

You had it?
If you mean I had support because I used the word friends, I use that term pretty loosely. They were my roommates and tolerated me up until they were tired of my shit.

Edit: No, sorry, I'm referring to the results section of the study where they talk about the fact that this is a small slice of a broader picture where toxoplasmosis -> stress -> political views. Because that seems like it's the "point" of this study. You have a mild chronic condition that affects a lot of people pretty much uniformly and adds stress. So if you see a difference in infected/not-infected then you have a strong case that more stress -> more conservative.

> It was suggested by that these associations might be the results of a mild chronic stress caused by the toxoplasmosis infection instead of the result of the toxoplasmosis itself. The presence of a chronic stress not only explain the presence of behavioral and political differences with the non-infected control group, but also the presence of sex differences in these behavior and ideologies as different responses to chronic stress in the two sexes, involving differences in the immune system response and in the coping strategies used

> previous studies showed that infected subjects scored lower in novelty seeking, a factor that contributes to a conservative and political opinion

I believe the parent of your response was asking if you had been diagnosed with toxoplasmosis, rather than support.
No, I mean toxoplasmosis. Your original comment seemed to imply you had a personal experience that lent credence to the study's result.
I thought it was an interesting premise going into the article, but the individual results are all over the map, and vary a significantly between men and women in the study. Correlating those with political affiliation seems dubious to me.
They say specifically that this is actually a point in favor of the association. The reason being that men and women deal with stress in diametrically opposed ways (they cite two other studies) and that being infected increases the stress response behaviors in both sexes.
Yeah. My initial thought was "it's going to be very hard to unpick any possible causal relationship of Toxoplasmosis to political affiliation from likely regional and income level variation in Toxoplasmosis, and this study doesn't even control for those.

It's also a study with a low number of participants, and none of the political factors are statistically significant for men and statistically significant for women. Surprised it was published tbh, although I guess it's better to publish inconclusive results to interesting hypotheses than encourage p-hacking...

There also is nothing about correlation vs causation, people who own cats are a distinct group with distinct behaviors.
Did not control for cat ownership AFAICT.
Anyone who has spent time on OKCupid can speak to the correlation of cat ownerships and political perspective, and the more cats owned the more magnified the political/social passion.
Does that lay intuition match with the proposed findings in TFA? I can copy the relevant sentence from the abstract, in case you didn't see it:

> Infected women scored higher in tribalism and lower in cultural liberalism

We picked terrible words for political stuff. Cultural liberalism is a pro free speech, "classical liberal"[0] (in modern times considered conservative) view.

> Cultural Leftists are people who believe “that minorities must be protected from psychological harm arising from forms of dominant culture, and that a radical transformation of science, institutions, narratives and culture can redistribute power from dominant to subaltern groups.”

> Cultural Liberals, on the other hand, “prioritise freedom of expression, equal treatment without regard to identity, the scientific method, freedom of conscience and the primacy of classical liberal traditions of law.”

> And finally, Cultural Conservatives are people who “prioritise the defense of national, ethnic and religious traditions. The dominant form of cultural conservatism in Britain is cultural patriotism.”[1]

[0]https://en.m.wikipedia.org/wiki/Classical_liberalism

[1]https://iea.org.uk/the-rise-of-cultural-socialism-a-review-o...

We must also consider where we source our definitions from. The IEA is a right-wing think tank. They have a vested interest in promoting certain points of view. And to portray those opposed to them in certain ways.

https://en.wikipedia.org/wiki/Institute_of_Economic_Affairs

First one that I found and it matches with my education. Happy to use any other you provide, but liberalism as a concept isn't something only occupied by the left wing even though they tend to be conflated.
It's really the portrayal of "cultural leftism" that leaves something to be desired. It's framed in such a way to make "cultural leftism" seem not only more paternalistic than they would describe their goals but to portray the issues facing minorities as more abstract and ephemeral than they actually are.

I notice how you only focus on the defensible definition as if the conflation of liberalism with some conservative goals could be the only objection to your post.

You mean "the more cats owned the more Democratic they vote?" Just making sure.
Weird, I've only encountered the exact opposite.
Based on the actual article, it's more like "the more cats owned, the more liberal/progressive/socialist men vote and behave, and the more conservative/tribal/fascist women vote and behave." Which fits well with my experience tbh. The 5+ cat ladies I know are all surprisingly conservative.
I have one long-time cat lady in my family and she is extremely liberal.
If so, then we're not that far off from it being spun as "cats cause anti-Patriotic" beliefs, followed by a witch hunt.
I own 3 cats by accident, and I didn't really "get" owning a cat before the first one's mom decided to abandon her new born kitten right in front of my house hahaha. Yet I don't think my political beliefs have really changed since, but maybe I need more cats for that to happen!
They mentioned that cat ownership does not strongly correlate with toxoplasma infection. There are other places to get the parasite from, which is why it's so prevalent.
Extremely poor wording in the first page or so:

> This study showed Toxoplasma-infected and Toxoplasma-free participants of our cross-sectional study differed in three of four factors of PI34, scoring higher in Tribalism and lower in Cultural liberalism and Anti-Authoritarianism.

- Is the author referring to the infected or to the free group here?

> The stress-coping hypothesis suggests that many toxoplasmosis-associated changes, e.g., higher extroversion in infected women and lower in men, or lower suspiciousness of infected women and higher in suspiciousness of infected men (all in comparison to non-infected peers) can be interpreted as gender-dependent stress coping reaction.

- Using “among infected men/women” in place of “of” would add a lot of clarity here.

I believe I’ll stop reading the article.

I believe the authors are Czech, so I would give them a bit of slack regarding the language, they are not native English speakers.
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Good to keep in mind, and I shouldn’t be overly harsh.

I considered the possibility and discarded it, given that the word choices so strongly resemble poorly-spoken native English speakers whom I have personally known. But I could have confirmed by looking.

Is there any way to tell if you're infected?
Do you have any hazy memories of situations eerily similar to this?

https://imgur.com/a/OrOtoPu

I guess I don't have it then, since I don't look like that. But that picture is a gem, even if I'd guess it's not very scientifically accurate!
Yes, there are IgG and IgM tests given to pregnant women, because the parasite can cause miscarriage or stillbirth.
Interesting that many scientists now think that any behaviour changes are not due to the parasite controlling the brain (which is how the parasite spreads in rats and cats!) but due to reactions dealing with long term stress caused by the infection.

One could assume that other long term pain that causes stress could see the same results in behaviours and the associated sex differences.

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Suppose this is accurate; how difficult/expensive is it to get tested for this, and if you have it, is there a cure?

Regardless of the effects it may or may not have on the brain, the paper mentions that "the differences might be side-effects of long-term mild inflammatory reaction", and for general health reasons I'd certainly prefer not to have permanent long-term mild inflammation.

There are treatments today, but they are mostly exotic drugs today because the parasites are thought to be harmless.

Martin Shkreli (pharma bro, however it's spelled) got into a lot of hot water for buying up a toxoplasmosa treatment and jacking the price by 100x.

"responders via an online survey" so there's a self-selection bias. You are selecting the people that chose to seek out a diagnosis of this infection, and such people are probably more neurotic and anxious.

Also did they control for age, relationship status and number of cats owned? Multiple cats owned is sometimes caused by loneliness in my experience so the causality may be easy to mix up.

I don't think this is true; it looks like they collected a pool of participants, asked them questions, and then found out who was/wasn't infected. See the "Materials and Methods" section.
> We measured beliefs and values of 2315 responders via an online survey (477 Toxoplasma-infected) using the Political Beliefs and Values Inventory (PI34). This study showed Toxoplasma-infected and Toxoplasma-free participants of our cross-sectional study differed in three of four factors of PI34,

s/study/internet poll/g

Flegr, author mentioned many times in article is bizarre Czech scientist who predicted streets full of dead bodies because of covid. You cannot take this man seriously. He also looks funny.

https://en.m.wikipedia.org/wiki/Jaroslav_Flegr

It actually happened in Indonesia - people died en masse in their homes, died in hospital's front yards, hospital's hallway, etc ; too many got infected, that the healthcare system simply unable to keep up. We even experienced severe medical oxygen shortage for months.

The only reason they didn't die on the streets was because we're under lockdown at the moment. So instead dying on the streets, they died indoors.

If this is self report, most people dont know their status of infection.