An Overview of One Health Concept Focusing on Toxoplasmosis

The "One Health" concept is a universal approach to sustainably balancing and optimizing the health of humans, animals, and ecosystems. This approach is based on the health of humans, domestic and wild animals, and plants in a wider environment in which self-renewable ecosystems exist, with essential characteristics of integration, unifying and holistic perspective. Toxoplasmosis, one of the most common zoonotic infections in both terrestrial and oceanic ecosystems in the world, is an ideal model disease for the "One Health" approach. Toxoplasmosis is a zoonotic disease caused by the obligate intracellular pathogen protozoan Toxoplasma gondii. In the life cycle of T. gondii, the definitive host is domestic cats and felines, and the intermediate hosts are all mammals (including humans), birds and reptiles. The infected cats have primary importance and play a crucial role in the contamination of habitats in the ecosystems with T. gondii oocysts. Thus, ecosystems with domestic cats and stray cats are contaminated with cat feces infected with T. gondii oocytes. T. gondii positivity has been scientifically demonstrated in all warm-blooded animals in terrestrial and aquatic habitats. The disease causes deaths and abortions in farm animals, resulting in great economic losses. However, the disease causes great problems in humans, especially pregnant women. During pregnancy, it may have effects such as congenital infections, lesions in the eye and brain of the fetus, premature birth, intrauterine growth retardation, fever, pneumonia, thrombocytopenia, ocular lesions, encephalitis, and abortion. The mechanism of death and abortion of the fetus in a pregnant woman infected with T. gondii occurs as a result of complete disruption of the maternal immune mechanism. The struggle against toxoplasmosis requires the universal collaboration and coordination of the World Organization for Animal Health, the World Health Organization and the World Food Organization in the "One Health" concept and integrative approaches of all responsible disciplines. Establishing universal environmental safety with the prevention and control of toxoplasmosis requires the annihilation of the feces of the infected cats using suitable techniques firstly. Then routinely, the monitoring and treatment of T. gondii positivity in cats, avoiding contact with contaminated foods and materials, and development of modern treatment and vaccine options. Particularly, mandatory monitoring or screening of T. gondii positivity during the pregnancy period in humans should be done. It would be beneficial to replace the French model, especially in the monitoring of disease in humans. In this article, the ecology of toxoplasmosis was reviewed at the base of the "One Health" concept.