Bounding through a thicket and sweating underneath an impermeable biohazard suit, the village headman chased a woman he suspected had Ebola. She dashed away. Her daughter had recently died of Ebola at a hospital, and she feared the headman would ship her to the hospital, where a malevolent force might cause her to suffer the same fate.

Indeed, Ebola response workers did intend to isolate the woman. In quarantine, they'd monitor her for symptoms of the deadly disease and, if signs surfaced, hospitalize her.

Since the day the woman ran away, several people in Tigbonor, a village in Sierra Leone, had spotted her under the shroud of darkness. "At 2 a.m., the woman sneaks chop," or food, says N'Baimba Conteh, the headman.