My wife got a routine test for toxo during her first pregnancy, and we had a bit of a scare when that came back positive; she needed an amnio, months of antibiotics, regular monitoring. Of course being French we already had a high base rate, but we were also cat people back then.
Just how large are those statistically significant effects, would be my first question. How well replicated the studies, my second. I wouldn't bother doing much about something that is small or somewhat anecdotal.
From this paper
Consistent and significant differences in Cattell’s personality factors were found between Toxoplasmainfected and -uninfected subjects in 9 of 11 studies, and these differences were not the same for men and women.
and
...Those with latent infection performed significantly more poorly (analysis of covariance, P = 0.011) and appeared to lose their concentration more quickly, although the effect of the infection was modest and explained less than 10% of the variability in performance. Similar results were recently obtained in 2 (unpublished)
Toxoplasmodi gondii is a parasitic protozoa who's primary host is cats but also infects other mammals, primarily mice and rats but including humans, as part of its life cycle. Infection by Toxoplasmodi gondii is called Toxoplasmosis and may be acute (flu like symptoms) or latent.
Toxoplasmosis is extremely common. Worldwide, about 30% (US 11%; France 88%!) of people about of people have Toxoplasmosis.
Toxoplasmosis is known to cause behavioral changes in rats:
Observational studies suggest that latent Toxoplasmosis may also cause behavioral changes in humans (source paper). The observed differences between infected people and non-infected people include: