White man lives with jungle tribe and brings deadly disease

White man exploring jungle comes upon isolated tribe, is accepted by them. He decides to live with them. Takes a wife, has a child, and then a deadly disease/sickness starts striking others and his new family. I don’t remember exactly how it ends just remember sadness. Probably 1980s or 90s but not sure. Don’t recall title or actors.

at play in the fields of the lord?