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Toxoplasmosis – A Global Threat (2014)

by 0x456 on 6/23/21, 12:11 AM with 54 comments

• by optimiz3 on 6/23/21, 2:25 AM

  Cats have the evolutionary benefit of being cute to humans. This allows them to be one of the most invasive species in the world.

  Case in point is Hawaii; attempts to bring the wild cat populations under control are immediately met with resistance from animal rights groups. This is in spite of the ongoing destruction to wild bird populations. One also has to be extremely careful about washing local vegetables, due to cats spreading toxoplasma.

• by felixbraun on 6/23/21, 2:35 AM

  It seems to be very unlikely that brain cysts (that might affect cognition) can form in immunocompetent people — a pathological study of AIDS patients showed cysts in ~20%; background seropositivity in France (where the study was conducted) is ~40%.

  Conclusion by the authors: the amount of toxoplasmic agents appeared to be related to the degree of deterioration of the immune status.

  > Neuropathological studies in the brains of AIDS patients with opportunistic diseases: https://pubmed.ncbi.nlm.nih.gov/8518200/

• by adamnemecek on 6/23/21, 2:21 AM

  The author of this paper, Jaroslav Flegr (https://en.wikipedia.org/wiki/Jaroslav_Flegr), was considered a crackpot for a long time.

  There was a profile on him in the Atlantic in 2012 https://www.theatlantic.com/magazine/archive/2012/03/how-you...

• by giantg2 on 6/23/21, 2:32 AM

  Everyone is mentioning cats. 30% of the beef in the US contains toxoplasm gondii. Now, a deep freeze for more than 24 hours will kill it, but how many people eat fresh beef and less than well done? This is part of the reason they recommend pregnant women not eat beef that is cooked less than well done.

• by rubicon33 on 6/23/21, 2:14 AM

  I love studies like this. I believe that as science progresses, we're going to see a lot more conclusions like this that previously "benign" things were actually causing problems, or setting the body up for later issues, we just didn't know it.

  Toxo is a perfect example. Chicken pocks is another. HPV a third.

  Personally I believe "alergies" are actually the result of a viral infection probably from the common cold, that sets off a long term hyper reaction to airborn particles and pathogens. So things like pollen in the air sets off a huge response whereas for some people who never were infected with the virus, they don't get "alergies".

• by jakubmazanec on 6/23/21, 5:31 PM

  Please ignore this "study" and whatever Jaroslav Flegr says. At my university he was mocked for his misuse of statistics - he does it even in this article, giant models with huge sample sizes finding correlations everywhere with p < 0.1.

  Also, in this article https://parasitesandvectors.biomedcentral.com/articles/10.11... he says that "pathogen responsible for mood disorders in animals-injured subjects is probably not the protozoon Toxoplasma gondii but another organism; possibly the agent of cat-scratched disease – the bacteria Bartonella henselae." So did he discover yet another behaviour change inducing organism, or is he simply a shitty scientist? Let's have a look: he recruits respondents via Facebook, they take 4 psychological questionnaires (which are usually not very reliable and shouldn't be used in giant correlation tables) and finds effect sizes ranging from eta2 = 0.004 to eta2 = 0.045. Just look at this table - https://parasitesandvectors.biomedcentral.com/articles/10.11... - results are significant because the sample size is 5000, but what are the practical differences? Barely 1 point on a scale that itself has reliability around 0.9 (which is good, but it still leads to standard measurement error greater than Flegr's effect sizes).

• by beaner on 6/23/21, 2:38 AM

  Does toxoplasmosis come up in a standard blood panel, or do you have to suspect it and test for it specifically?

• by slumdev on 6/23/21, 2:17 AM

  (2014)

  Definitely still a global threat in 2021, but not the disease that most people have on the brain right now. (Unless they own a cat.)

• by dempsey on 6/23/21, 4:10 AM

  This is remarkably similar to chronic lyme disease.

• by ck2 on 6/23/21, 3:16 AM

  Paper is from 2014, a few years later some scientists realized the answer is ironically, ivermectin.

  But good luck getting the NIH/CDC to mention that drug name right now.

• by echelon on 6/23/21, 2:05 AM

  Toxo is no joke. Apart from opening the door to other diseases and chronic inflammation, it also induces neurological changes we still barely understand.

  It might be a contributor to depression. What we do know is that it correlates positively with motorcycle deaths and risk taking behaviors [1]. Postmortem tests show this. (My old immunology professor used to say that toxoplasma indirectly leads to more organ donation.)

  Keep your cats indoors. Or get a dog instead.

  Toxo evolved to fuck with mice brains and make them not fear being eaten. Your brain operates on similar biochemistry.

  Be careful.

  [1] Not a direct citation, but similar claims : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC117239/