A recent study shows limited evidence supports the hypothesis that cat ownership in pregnancy and childhood could lead to psychosis in later growth stages.
The study results could overturn a general psychological hypothesis which laid the blame of people getting crazy on cats.
This kind of domestic pets is the definitive host for a parasite named toxoplasma gondii (T. gondii) that causes toxoplasmosis infections in people.
Such infection was associated with the possibility of human developing a number of mental health disorders, particularly schizophrenia.
Published Wednesday on the Psychological Medicine journal, the report was conducted using birth cohort data from the Avon Longitudinal Study of Parents and Children, a cohort research on more than 15,000 British families with babies born between 1991 and 1992.
Researchers from University College London studied about 5,000 children and their families, with categorized study groups of children aging four and 10 years, teenagers at 13 and 18 years old, as well as their mothers, all with cats in their homes.
Statistical analysis "strongly indicates that cat ownership in pregnancy or early childhood does not confer an increased risk of later adolescent PEs (psychotic experiences)," according to the study report.
Lead author of the study, Francesca Solmi, stressed that even if T. gondii is a driver of mental health disorders, owning a cat does not amount to an additional risk for developing psychotic symptoms.
"Previous studies reporting links between cat ownership and psychosis simply failed to adequately control for other possible explanations," Solmi said in a press release.
"Once we controlled for factors such as household over-crowding and socioeconomic status, the data showed that cats were not to blame," she added.
Nevertheless, the research team suggested that "pregnant women should continue to avoid handling soiled cat litter, given possible T. gondii exposure."
The new study covered a larger range than previous ones. Still there might be uncertainties as the participants haven't reached the typical onset ages of several mental disorders, which could not get mature until the participant turns 25.
Solmi defended, however, that early signs of mental illness would be detectable when the participants were screened for psychotic experiences at ages 13 and 18.