California Valley Fever Cases Hit 2,197 as Climate Change Pushes Fungus Beyond the Southwest
Updated
Updated · The Weather Channel · May 13
California Valley Fever Cases Hit 2,197 as Climate Change Pushes Fungus Beyond the Southwest
5 articles · Updated · The Weather Channel · May 13
California has recorded at least 2,197 Valley Fever cases in 2026, already nearing the 2,996 reported in all of 2025 as infections spread north of their traditional range.
Hotter, drier conditions followed by extreme rain help coccidioides fungus bloom in soil and then turn airborne, with spores carried by dust storms, hurricane winds and floodwaters.
Oregon and Washington are identifying more cases, and experts say the fungus could keep expanding into the Midwest and potentially reach Canada within decades.
Valley Fever often resembles a cold or flu but can last weeks to months like pneumonia; in a small share of cases it spreads through the bloodstream and can cause lethal meningitis if untreated.
Doctors warn travel is turning it into a national disease in disguise, because visitors can inhale spores in the Southwest and develop symptoms later in states where clinicians may miss the diagnosis.
As 'fungal storms' push north, can our health system adapt faster than this climate-driven disease?
This flu-like illness is sweeping the US. Why does it take doctors nearly a month to diagnose it?
Dogs are early victims of this spreading fungus. Could they be the key to predicting the next human outbreak?
Valley Fever’s Expanding Footprint: The Human, Economic, and Climate Costs of a Growing U.S. Epidemic
Overview
Valley Fever, caused by the Coccidioides fungus, is rapidly becoming a major public health concern due to an unprecedented surge in cases and a swift geographic expansion across the American West. This spread is closely tied to environmental changes, especially those driven by climate change, such as drought and dust storms, which help the fungus thrive and disperse. Many cases go undiagnosed, making the true scale of the problem much larger than reported. As new areas like Salinas, California, are increasingly affected, the need for greater awareness, improved diagnosis, and stronger public health responses is more urgent than ever.