The idea that toxoplasmosis is a contributing factor to mental illness is decades old. This paper is merely an incremental restatement of that hypothesis. The abstract says, "Instead of just alleviating symptoms with drugs, the parasite x genotype x stress model emphasizes that schizophrenia treatment should focus on detecting and treating possible underlying microbial infection(s), neuroinflammation, gut dysbiosis, and chronic stress."

Chris Palmer's treatment emphasizes reduction of inflammation and dysbiosis via dietary means. This hypothesis is not limited to treatment of schizophrenia, but also other mental illness, such as bipolar disorder. The following two recent podcasts are illuminating.

https://www.psychiatrypodcast.com/psychiatry-psychotherapy-p...

https://www.rickhanson.net/being-well-podcast-evolving-our-a...