Abstract:

Objective To assess the risks of infection and transmission of Toxoplasma gondii in domestic cats in urban Shanghai through analysis of the risk factors for the release, exposure and transmission of this obligate intracellular protozoan the domestic cats in urban households. Methods The risk assessment framework of Toxoplasma gondii infection in domestic cats was constructed by reviewing the literature reports and monitoring from Shanghai Animal Disease Prevention and Control Center. Based on the results of hazard identification and risk factors of Toxoplasma gondii infection in the domestic cats, the scenario tree of Toxoplasma gondii transmission in domestic cats population was analyzed and mapped. Finally, the risks of Toxoplasma gondii infection and transmission in the domestic cats were qualitatively characterized by potential pathogen release, exposure and consequences. Results The risk factor of Toxoplasma gondii release in domestic cats in urban Shanghai was “cat source”, and the risk level of pathogen release was rated as “medium”. Exposure risk factors were related to feeding methods, feeding raw meat/animal offal, co-ownership of cats and dogs, escape and hunting behavior, for which the risk level of exposure was rated as “high”. The residents in urban Shanghai area exhibited higher health literacy, stronger awareness to scientifically raise pets, for which the risk level of consequences was graded as “low”. According to the risk combination matrix between different steps, the risk of infection and transmission of Toxoplasma gondii was “low” in the domestic cats in urban Shanghai. Conclusion Domestic cats in urban Shanghai are provided with the environmental conditions for toxoplasmosis release and exposure, which are potential risks for human infection with toxoplasmosis, yet the risk level is generally low.

Key words: Domestic cats, Toxoplasma gondii, Risk factors, Qualitative risk assessment, Transmission risk, Shanghai