In 1993, an interesting example of ecosystem dynamics occurred when a rare lung disease struck inhabitants of the southwestern United States. This disease had an alarming rate of fatalities, killing more than half of early patients, many of whom were Native Americans. These formerly healthy young adults died from complete respiratory failure. The disease was unknown, and the Centers for Disease Control (CDC), the United States government agency responsible for managing potential epidemics, was brought in to investigate. The scientists could have learned about the disease had they known to talk with the Navajo healers who lived in the area and who had observed the connection between rainfall and mice populations, thereby predicting the 1993 outbreak.
The cause of the disease, determined within a few weeks by the CDC investigators, was the hantavirus known as Sin Nombre, the virus with “no name.” With insights from traditional Navajo medicine, scientists were able to characterize the disease and rapidly and institute effective health measures to prevent its spread. Though not as common any more, infections from hantavirus still occur. You can read more about hantavirus in this CDC article.