Acknowledgments This work was supported by the Priority Program of the German Research Foundation (DFG) (RI 1849/2-1 and 4-1) and the Wellcome Trust (102705). We gratefully acknowledge our Ethiopian partners at the Armauer Hansen Research Institute, Addis Ababa. Rawleigh Howe for excellent supervision of flow cytometry analysis performed at the Armauer Hansen Research Institute and Selfu Girma, Birtukan Endale, Genet Amare and Hareg Yetesh for technical support during the field trips and laboratory work. Supplementary Material The Supplementary Material for this article can be found online at http://www.frontiersin.org/articles/10.3389/fimmu.2018.00263/full#supplementary-material.Peer reviewedPublisher PD