As the climate warms, the southwestern U.S. is increasingly experiencing weather whiplash as the region swings from drought to flooding and back again.
As a result, the public is hearing more about little-known infectious diseases, such as valley fever . In May 2024, about 20,000 people attended a music festival in Buena Vista Lake, California. In the months that followed, at least 19 developed valley fever , and eight were hospitalized for their infection.
This outbreak follows a dramatic increase of more than 800% in valley fever infections in California between 2000 and 2018. In 2023, California reported the second-highest number of valley fever cases on record , with more than 9,000 cases reported statewide. And between April 2023 and March 2024, California provisionally reported 10,593 cases—40% more than during the same period the prior year.
The Conversation U.S. asked Jennifer Head , Simon Camponuri and Alexandra Heaney —researchers specializing in the epidemiology of valley fever —to explain what valley fever is, and what might explain its rise in recent years.
What is valley fever, and how do you get infected? Valley fever is the common name for a disease called coccidioidomycosis , which is an infection caused by pathogenic fungi from the Coccidioides genus. The fungi are primarily found in arid soils of the southwestern United States , as well as parts of Central and South America. When the fungus has access to moisture and nutrients, it grows long, branchin.
