The single-celled parasite toxoplasma infects all warm-blooded animals, including approximately one-third of humans. Only cats maintain the parasite's sexual stage
However, rodents with latent toxoplasmosis, which show no physical sickness, behave abnormally.
Most significantly, infected rodents are less wary of dangerous stimuli like cat scents. Latent cysts modify brain structure, hormones, and neurochemistry.
Some research imply that the parasite's immune response induces brain inflammation, causing mice's behavioral abnormalities.
Similar neurological abnormalities are seen in latent toxoplasmosis patients. Toxoplasma infection increases risk-taking, violence, impulsivity, suicide, and homicide.
Latent toxoplasmosis and schizophrenia are well linked, thus meta-analysis to establish if cat ownership is also linked to schizophrenia.
To understand cat ownership as a mental disease risk factor, further high-quality studies with large, representative samples are needed.