Jawaruwa Waiapi and his family walk through early morning fog at the Manilha village in the Waiapi indigenous reserve in Brazil's Amapa state on Oct. 13, 2017.

Tribal chieftain Tzako Waiapi perfectly remembers the day almost half a century ago when his hunting party stumbled across a group of white adventurers in the Amazon rainforest. Within months, nearly everyone in his entire tribe had died from disease.