Toxoplasma gondii infection and neuropsychiatric disease: current insight

Toxoplasma gondii has always been associated with severe medical disease when acquired congenitally or under immunocompromised conditions. However, in the last decade, intensive research has shed light on Toxoplasma gondii as a latent chronic infection producing distinct neuropsychiatric symptoms and alterations in its intermediate hosts, such as humans and rodents. The peculiarities described range from the well-established attenuated odor aversion paradigm toward cat urine, in infected rodents to significant associations with psychiatric disorders such as schizophrenia or bipolar disorder, to cognitive impairments, and increased traffic accidents. In relation to what has already been investigated to date, how could we explain such effects on the basis of what we know about the complex interplay of this intracellular permanent parasite and its host? This review systematically screens the recent literature, presents results from a physician's point of view, and discusses possible mechanisms and further research lines.