Epidemiology of Animal Trypanosomiasis

Abstract

Trypanosomiasis, alternatively known as trypanosomosis, is the name of several diseases in vertebrates, induced by parasitic protozoans belonging to the Trypanosoma genus. The best-studied species is Trypanosoma brucei with two subspecies: Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, which cause Human African trypanosomiasis (HAT), also known as sleeping sickness. Moreover, African animal trypanosomiasis (AAT) poses a substantial risk of spillover and the transmission of different species and strains among populations, impacting both livestock and wildlife. Increased human activity and pressure on land resources are increasing wildlife-livestock-human infections. In addition to the role of human Trypanosoma reservoir, animals can become infected and ill as a consequence of the activity of other forms of trypanosomes, such as Trypanosoma congolense, Trypanosoma vivax, Trypanosoma brucei brucei, Trypanosoma simiae, Trypanosoma evansi, and others. Tsetse flies (Glossina spp.) can transfer parasites through their salivary glands or, in rare instances, by congenital transmission. Chagas disease (Morbus Chagas), also known as American trypanosomiasis, is a chronic infection caused by Trypanosoma cruzi. The competent vectors of Chagas disease are bed bugs from the genera Triatoma, Rhodnius, and Panstrongylus. All major groups of mammals, including Artiodactyla, Chiroptera, Primates, Carnivora, Rodentia, Cingulata, Pilosa, and Didelphimorphia, have been shown to participate in the transmission cycle of T. cruzi. Chagas disease is endemic in Central and South America. Human and animal trypanosomiases continue to present a major human and animal public health threat globally. The high genetic diversity of Trypanosoma spp. requires further research to prevent cross-species transmission, which could affect animal, human, and environmental health. In this chapter, we delve into the most significant Trypanosoma species, their epidemiology, distribution, importance for biodiversity, and public health.