Acknowledgment
This work was supported by the David and Lucille Packard Fellowship for Science and Engineering (DIB), the Howard Hughes Medical Institute (Early Career Scientist award to DIB), and by NIH NIAID grant 1R01AI123659-01A1. Field sampling in 2009 was made possible by assistance from Todasporn Rodbumrung, Chris Harrison, Will Shim, Yuexin Jiang, Will Stutz. Will Shim provided parasite information in Table S2.