With all the evidence of toxoplasmosis links with behavior changes, obsessive compulsive disorder, schizophrenia, depression, and bipolar syndrome, all I can think of is the classic stereotype of the crazy cat lady with 30+ cats.
Or maybe, just maybe, she started out just fine with just one or two cats and then got toxoplasmosis, which caused her to become a bit antisocial, and neurotic. The more socially removed she got,the more time she spent with her cats—possibly renewing her infection and increasing the levels of toxoplasma gondii in her brain. Then shortly after, her cats became more of an obsession causing her to collect more and more cats.
Ya know, it really would be in the parasite’s best interest to alter people’s behavior to collect cats and thereby create such a fabulous breeding ground for itself.
p.s. Carl Zimmer’s blog, The Loom, has good article on possible some national personality differences due to differing levels of toxoplasmosis infections between citizens of different nations.