The phenomenon of desert storms sweeping across the United States is not just stunning to behold; it poses serious health risks. Phoenix, Arizona, witnesses this brown wall of dust almost routinely, but it carries more than just sand. It can harm those exposed to it.
Recently, the U.S. has been facing an increase in what experts are dubbing “fungal storms.” These storms bring with them a disease that many doctors may not even know about.
What is Valley Fever?
The disease technically called Coccidioidomycosis, is commonly referred to as Valley Fever. It originates from the fungus Coccidioides, which resides in the dry soil of the American Southwest, particularly in Arizona and California. As long as the spores remain underground, they pose no threat. However, they become dangerous when stirred up and released into the air by the wind.
Why Are Cases Rising?
Numbers tell a significant story. In 2008, there were approximately 7,500 reported cases in the U.S., a number that soared to over 21,000 by 2023. Experts estimate the true figure could reach up to 360,000 infections annually, many of which go unnoticed. California alone registered over 12,500 cases in 2024—an all-time high.
The primary culprit is a well-known factor: climate change. Drought, heat, and parched soils create ideal conditions for the fungus. For instance, the Great Salt Lake in Utah has shrunk to a quarter of its usual volume; the exposed lakebed is turning into dust that can affect nearby towns.
A Wandering Fungus
Just a few decades ago, Coccidioides was mainly limited to the Southwest. It has now been detected as far north as Oregon and Washington, with projections suggesting it could reach North Dakota and Minnesota—and even Canada—by the end of the century. “Fungi are incredible adapters,” says Tom Chiller, a former director at the CDC. Environmental changes are paving the way for more areas where these spores can thrive.
How Dangerous Is It Really?
Most individuals who inhale these spores experience no symptoms. About three out of five confirmed cases manifest either no symptoms or only mild, flu-like symptoms. However, a minority can face serious health issues such as fever, fatigue, rashes, joint pain, cough, and chest pain. John Galgiani, who has studied the disease at the University of Arizona since the 1980s, notes, “For many patients, it is more exhausting than the flu,” which can incapacitate them for weeks. In severe cases, Valley Fever can lead to pneumonia and may even reach the brain and spinal cord, resulting in meningitis. For a few hundred individuals each year, the disease can be fatal.
Treatable but Often Unrecognized
The good news is that Valley Fever can be treated with antifungal medications like fluconazole. The downside is that these drugs can have severe side effects, and in serious cases, patients may need to take them for a lifetime. The real challenge lies in diagnosis; many doctors aren’t aware of the condition, resulting in patients undergoing multiple ineffective antibiotic treatments before anyone considers the fungus.
Who Needs to Be Extra Cautious?
Essentially anyone can be affected. “It is an equal-opportunity pathogen,” Galgiani states—those exposed to the spores have the same risk as others. However, those who work frequently in dusty environments—such as agricultural workers, construction workers, firefighters, archaeologists, and soldiers—are at a heightened risk. Notably, severe cases appear to affect people of African and Filipino descent more frequently, though the reasons for this are still unclear.
What Truly Protects You?
To avoid Valley Fever, the best strategy is to steer clear of dust. During dust storms, it’s advisable to stay indoors, keeping windows and doors closed. Air purifiers can help reduce fine particulates in indoor air. As of now, there is no vaccine available, but researchers are working on one. Until then, understanding that there is an invisible threat in the dust remains crucial.
