Parasites and politics

What if you learned that your politics (or religion?) were influenced by a parasite you carried. Not something that made you irrational, but that tweaked your emotions or what you cared about. Like boosting your sense of empathy or other-identification, making you more left/libera. Or something else, for conservatives or libertarians [I don't feel up to coming up with a non-insulting plausible emotional modification for them, maybe someone still in those mindsets can]. Would you want a cure? Would you urge people to get the parasite? Likely, what other effects the parasite had might might matter; that could range from fairly neutral (like Toxoplasma in humans) to something majorly negative.

What if you learned instead that such parasites tilted people toward your political opposition?


This was probably the premise of a Greg Egan short story, but it's been a while...