From JSTOR Daily by James MacDonald:
In 1993, in the four corners region of New Mexico, young healthy people began suffering generic flu-like symptoms. Within an eight-week period, ten people had died, their lungs filled with fluid. Many of the victims were members of the Navajo Nation. A perplexed task force of state, federal, academic, and tribal officials soon convened to find the cause. Initially named Four Corners Virus, the mysterious illness was later dubbed Sin Nombre, which means “without name.” Despite intense effort, the task force was unable to crack the case; experts had never seen anything like it.
Except that some people could recall something like this before. As described by anthropologist Maureen Trudelle Schwarz in Ethnohistory, the Navajo authorities turned to an unorthodox source of help: the tribe’s elders. The elders provided a group of healers to speak to the epidemiologists.he Navajo have a long oral tradition passed from generation to generation, spanning hundreds of years or more and predating the written language.
Some of these histories spoke of previous outbreaks of rapid onset, lethal diseases among the Navajo in 1918 and 1933. The cause, they reported, was “disharmony,” which leads to excess. All of the years when the sickness struck, including 1993, had had excess rain and snowfall, leading to a bumper crop of piñon pine nuts. The nuts led to a boom in the local rodent population.