Overview
- A PLOS One study published this week analyzed public data from 93 countries and found a positive association between national cat density and reported happiness and a negative association between Toxoplasma gondii exposure and happiness.
- Researchers reported the unexpected result that countries with more cats tended to have lower levels of T. gondii exposure rather than higher infection rates.
- The paper used national-level (ecological) data, so the authors warn the analysis cannot prove that owning cats causes greater happiness or that T. gondii causes less happiness.
- Study authors propose that socioeconomic and pet-management factors—such as indoor pets, commercial food, veterinary care and better sanitation in wealthier countries—likely explain the paradoxical pattern.
- The team recommends follow-up individual-level and longitudinal studies that combine socioeconomic measures and biological surveillance and notes potential public-health and mental-health implications if a causal link is found.