[kadoban]

We know our gut biome in general has a huge effect on our behavior as well (most obviously around food choices), though I don't think those are technically "parasites".

Less interesting but still worth noting, many infections cause us to sneeze and cough in ways that increase the spread of the infection to others. Ain't evolution grand.

Another one, I remember that late stage Syphilis in at least some cases causes sexual promiscuity.

[joaomacp]

I've also read that the cold or flu virus makes us seek more human contact and feel more affectionate, supposedly overriding our mind in order to propagate the virus.

[geoduck14]

That explains a lot of bad decisions with the Corona Virus