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Comment by chasil | Hacker News Reader

We really ought to find a way to cure a latent infection of Toxoplasma gondii. I wonder if CRISPR could do it.

Last I checked, toxoplasmosis was curable:

>Most healthy people recover from toxoplasmosis without treatment. Persons who are ill can be treated with a combination of drugs such as pyrimethamine and sulfadiazine, plus folinic acid. [0]

Or is there something special about a latent infection vs an active infection?

[0] https://www.cdc.gov/parasites/toxoplasmosis/treatment.html

The latent infection forms cysts in the brain that remain for the rest of the life of the organism. These cysts cause the behavior changes in rodents that attract them to the smells of cats.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC106833/

"[The cysts] are more prevalent in the neural and muscular tissues, including the brain, eyes, and skeletal and cardiac muscles. Intact tissue cysts probably do not cause any harm and can persist for the life of the host without causing a host inflammatory response."

> forms cysts in the brain that remain for the rest of the life of the organism

where organism = mouse. We are neither mice nor live for one year and then die like mice do.

If you read the paper, you will discover that the infection is indeed life-long in humans.

If we cured toxoplasmosis, then there would probably be a ton of abandoned cats.

I don't follow your logic here...care to elaborate?

I think the joke the OP is making pokes at the parasite's "mind control" abilities; i.e. that it's somehow controlling the human mind to think cats are cute.

I wonder if it was the reason for the worshiping of cats in ancient Egypt [0]

[0] https://en.wikipedia.org/wiki/Bastet

Probably not, but I mean... who knows?

Minor alterations in human behavior over time eventually venerating our feline friends?

Yes but it's not a joke, it's an inference.

If I take it less seriously than intended, it's a joke.

The most common way to get infected is from cats. Specifically cat feces.

IIRC toxoplasmosis affects the brains of rodents making them less afraid of cats, which means that they're more likely to be killed and eaten by those cats, which spreads the infection to the cats. I think there have been claims that perhaps it also makes infected people like cats more in a similar fashion, which I guess is what GP is referring to.

Not the OP. Toxoplasmosis from what I understand can cause mice to lose fear of cats. So I think what the OP is suggesting is that toxoplasmosis is brain washing us to like cats and without it we would abandon some cats.

I thought it was associated with higher risk taking. The mice are less fearful in general, hence they may take risks that make them more likely to be seen/caught/trapped/eaten by the cat.

There's a story about a doctor (I think) who started to have a sixth sense for ordering toxo tests for people who came in to the ER with motorcycle injuries. The tests often came back positive. IIRC the high positivity was due the fact that toxo increases risky behavior in humans as well as mice.

It's still an open question why mice with toxo don't end up in hospital for motorcycle injuries. I have an inkling that it is correlated with the low rate of human toxo victims eaten by cats each year, but who knows.

Hey dang-- why is sibling comment by SandMan2233 flagged? It's a funny response to my tongue-in-cheek questions at the end of my comment.

I get it if someone wants to downvote a joke. But flagging is extreme, and I thought the upshot of your moderation system was to temper extremism.

Toxoplasma changes behaviour, GP is implying (likely facetiously) that liking cats is an influenced behaviour by the parasite.

We only have broad suspicions how behaviour affects humans, with different effects for men and women.

There is a theory that toxoplasmosis infection causes humans to acquire more cats. The analogy is that mice infected with it are more likely to be consumed by cats because they appear to have a lower fear response to felines

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