Where There Is No Doctor: A village health care handbook is the definitive remote-area health book and a great prepper book for those who find themselves in remote areas, especially tropical areas, and has useful information for all regions. It was based on David Werner‘s experiences at his Project Piaxtla in western Mexico This is one of the few books I recommend to pack in your bugout bag. I always have a digital copy in mine.
I have a free pdf version you can download here
Or you can buy the hardback version here: