I know several bird women. The problem is that instead of becoming extroverted because of an infection, they develop lung problems. It's much less romantic.

https://en.wikipedia.org/wiki/Bird_fancier%27s_lung

Cat people in general are noticably different from non cat people... Not really sure how but it's definitely a thing

But are they different because of the infection, or they are different and hence the infection. That is the question

I’m a cat person. In fact I have a cat, but just the one.

I’m not sure how that makes me generally different though? I’m not trying to be argumentative, I’m genuinely curious.

I am and have always been an introvert, but I’m friends with introverted dog people too. Other than that, I’m not sure what (for lack of a better term) stereotypical traits I would have that correlate with being a cat person?

Genuinely interested in observations.

There are 100% dog men but rather than "more dogs" they tend to go for "more dog".

There are also definitely "rat people", but not Splinter IYKWIM.

> Asking non-jokingly, how do we explain “cat ladies”?

It's a book/holywood cliché

Niche media hype.

There are other such media hypes which you can explain like that without involving a neurologically active parasite. For example the belief that whites are being systematically replaced by blacks/hispanics/muslims/jews/... Or the belief that there is a single supreme being in the sky, watching everything we do, having killed his son for humanities sins. There are no rational reasons to believe any of this, still, many people do, with lots of media helping them reinforce those thoughts in quite effective bubbles.

So-called niche media hype is the reason gp thinks cat women are the product of toxoplasmosis. A general explanation for cat women themselves (along with all your other examples) is culture.

It might be that the cats find the crazy lady.

Might be like some kind of filter effect.

Along the lines of Cat lady has 1000 cats arrive at her place over a period of years.

990 of those cats are like "Hell No!" and GTFO. But 10 are a matching kind of crazy and stick around.