It is a little surprising to me how little follow up there has been to Jaroslav Flegr's 2002 paper describing a relationship (although not necessarily a causal relationship) between latent Toxoplasmosis infection and road traffic accident rate. The original paper Increased risk of traffic accidents in subjects with latent toxoplasmosis: a retrospective case-control study has only been cited 24 times since then. Whilst that's quite respectable for a science paper it hardly suggests the large scale interest this paper deserves.
Using Web of Knowledge (available through the library website, or use the off-campus login) you can easily find the papers that cite Felgr and see which of them perform similar studies. Of the 24 citations the majority are either reviews, concern Toxoplasmosis in animals, or look at psychological effects in humans. A few of the papers look at behavioral effects in humans but only 3 investigate the road traffic accident angle.
Flegr's group found the same relationship in a totally different data set in the Czech republic:
Increased incidence of traffic accidents in Toxoplasma-infected military drivers and protective effect RhD molecule revealed by a large-scale prospective cohort study
and two studies in Turkey find similar results to Flegr:
Higher prevalence of toxoplasmosis in victims of traffic accidents suggest increased risk of traffic accident in Toxoplasma-infected inhabitants of Istanbul and its suburbs
Is Toxoplasma gondii a potential risk for traffic accidents in Turkey?