Direct testing for the parasite's DNA in the cerebral-spinal fluid (yeah, a spinal tap sorry) is sensitive, too. Attempting to detect it elsewhere (blood, etc.) works but isn't as reliable. This is more expensive but sometimes used when unsure. Otherwise, in combination with that, it's diagnosed symptomatically. It shows up on a brain scan if the lesions get big enough, not to be alarmist.
When an infection is latent, it's normally described as asymptomatic. But there is some reason to think, it might subtly affect humans neurologically in a similar way to how it seems to affect other mammals, like the wolves in this article. But this is controversial.
The behavioral changes are a different story.
I use immunosuppressive medication to manage a chronic condition, so I assume my immune function is worse than someone not using such, but better than e.g. someone undergoing chemotherapy.
Does this make me immunocompromised or not? Or, where does it place me on the scale? What precautions should I take?
It would be useful to understand how your medication interacts with this process.
https://m.youtube.com/watch?v=lXfEK8G8CUI
Somatic hypermutation has a small discussion in the Kerzegast book.
I understand that somatic hypermutation, by the removal of uracil, plays two roles, first in initial recognition of a pathogen, then second in tuning the response for variants.
As I understand it, this only happens in germinal centers, the lymph nodes.
https://www.scribd.com/document/664375598/IMMUNE-by-Philipp-...
This is a question for an infectious disease specialist.
In all seriousness, since this topic comes around every couple years, I've always wondered if we tested different populations of people based on career if we'd see some correlation. Cats are fairly ubiquitous across populations (but knowing if there's a higher prevalence in some would be important), so there's at least a chance for most people to be exposed I think.
> Landon Donovan Needs a Cat
> Could a brain parasite found in cats help soccer teams win at the World Cup?
> ...
> If we set aside the qualifying rounds (in which teams can play to a draw) and focus on matches with a clear winner, the results are very compelling. In the knockout round of this year’s tournament, eight out of eight winners so far have been the teams whose countries had higher rates of Toxo infection. If we go back to the 2006 World Cup, seven out of eight knockout-round winners could be predicted by higher Toxo rates. The one exception to the rule was Brazil’s defeat of Ghana, a match between two nations that each have very high rates. (Aside from having the winningest team in World Cup history, Brazil has quite a few cases of Toxo: Two out of three Brazilians are infected.)
> It gets better. Rank the top 25 FIFA team countries by Toxo rate and you get, in order from the top: Brazil (67 percent), Argentina (52 percent), France (45 percent), Spain (44 percent), and Germany (43 percent). Collectively, these are the teams responsible for eight of the last 10 World Cup overall winners. Spain, the only one of the group never to have won a cup, is no subpar outlier—the Spaniards have the most World Cup victories of any perpetual runner-up.
... and yes, that that's not a science paper. Slate is far from being a paper hosted at NIH. ... so...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7928503/
> Potential linkage between Toxoplasma gondii infection and physical education scores of college students
> ...
> The overall seroprevalence of T. gondii was 11.5%. The main risk factors related to T. gondii infection in college students were cat in the household and gardening or agriculture activity. Furthermore, in the basketball group and the soccer group, scores of T. gondii seropositive students were significantly higher than those of seronegative students, while in other sports there was no difference between scores of T. gondii-infected students and T. gondii uninfected students.
1) Almost everyone who has it got it from eating undercooked meat, not from cats. France has the highest rate of toxoplasmosis in the world because of their propensity for rare meats: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312802/.
2) Unless your cat lived a long part of it's life as an outdoor cat, it is very unlikely to have the parasite (like any parasite).
Corrected: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1118145/
Overall, eating raw or undercooked beef, lamb, or other meats; contact with soil; and travel outside the country were major sources of infection.
Contact with soil is from cats shedding oocysts, as covered earlier in the same extract, and while that doesn't necessitate owning a cat, I would classify it as exposure to cats (your neighbors outdoor cat shitting in your yard is still cat exposure to my sensibilities).
The association of cats and human toxoplasmosis is difficult to assess by epidemiological surveys because soil, not the cats, is the main culprit. Oocysts are not found on cat fur and are often buried in soil along with cat faeces. Therefore, direct contact with cats is irrelevant with respect to T gondii transmission, and soil contact is universal and difficult to avoid.
Which doesn't say cats don't matter, just that direct exposure doesn't matter. Soil exposure is exposure to cats through an intermediary, just not direct. It will still likely be affected by prevalence of cats in a population, even if not necessarily at a household level.
So, I think the article answers my original question to a degree, but I also think your claim that almost everyone that has it got it through eating meat with it in it is too strong given the sources you quoted (thanks a lot for posting them though, it's always nice to have data for a discussion!). If you think my reading of it is incorrect or I'm missing something, please let me know though.
Two questions, why do you care and what is anybody going to do about it? (The answer to the second question is “almost certainly nothing”)
There was a now discontinued (US) blood pressure medicine called guanabenz which studies were showing some effectiveness against the latent stage, but it’s no longer available.
So knowing might not matter that much.