Eco-epidemiology of tuberculosis in Maasai Mara Kenya: Conceptualizing sociocultural practices for One Health

Abstract

The control of tuberculosis has proven an ongoing challenge for public health. For pastoralists, those defined by their fundamental cultural relationship with livestock and migration in search of pasture and water, the complexity of tuberculosis control intersects with social and cultural practices that should be considered when designing interventions not as binary attributes of the community, but as a continuum within which the community lives and operates. The goal of the work contained within this thesis is to characterize Mycobacterium tuberculosis complex species (MTBC) in a high-exposure human-animal interface; explore the relevance of social and cultural factors; and evaluate the potential role of livestock movement in the transmission and control of zoonotic tuberculosis in the Mara ecosystem. In this dissertation, I document the co-circulation of multiple MTBC species in this ecosystem, with zoonotic tuberculosis substantially contributing to the overall burden, especially in villages adjacent to the Maasai Mara National Reserve, a protected wildlife area. Further, this work demonstrates that livestock movements not only mediate connectivity between villages within this ecosystem, but also interact with other factors to shape household tuberculosis patterns. Specifically, consumption of raw animal products, and movement of livestock for grazing or trade influence household tuberculosis occurrence, and reinforce the importance of zoonotic tuberculosis. Using data on livestock movement, this study demonstrates that dry season grazing patterns are important for enhancing the embeddedness of households’ in their community social networks, with villages adjacent to the Maasai Mara National Reserve as the most common destination for grazing. Overall, the work presented here reinforce the complexity of this issue within this ecosystem, and demonstrates that network-based control measures aimed at highly connected villages, have the potential to enhance the proactive development of targeted disease control programs as traditional and/or narrowly focused approaches for tuberculosis control are unlikely to work. Thus, in accordance with the current global wave of thinking, One Health approaches are also necessary and even required in this system. However, the operationalization of One Health approaches need to be culturally appropriate and tailored specifically to the characteristics of a locality and contextualized to its practices and structures.