Valley Fever is caused by a type of soil-dwelling fungus called coccidioides. Spores of this fungus go airborne in dry and dusty conditions, and when people breathe the spores, they can get sick.
In the past, Valley Fever cases were concentrated in dry areas of California like the San Joaquin Valley, Arizona, and East Texas.
But now, cases of Valley Fever are surging as the fungus spreads into areas that are becoming more hot and dry due to climate change, according to a report from California’s Office of Environmental Health Hazard Assessment (OEHHA).
In 2001, there were 4.3 reported cases of Valley Fever per 100,000 people. Twenty years later, in 2021, the number of cases had skyrocketed to 20.6 per 100,000 people, according to the OEHHA.
People in high-risk occupations for catching Valley Fever include agricultural workers and construction crews, but anyone who breathes contaminated dust can be infected.
The good news is that most people who breathe in spores of the fungus that causes Valley Fever do not get very sick, with limited respiratory symptoms that last for a few weeks or months.
The typical symptoms include fatigue (tiredness), cough, fever, shortness of breath, headache, night sweats, muscle aches or joint pain, and sometimes a rash on the upper body or legs.
The disease can be cured with anti-fungal medications, but a proper diagnosis is necessary first. This can be a problem when people travel to areas where Valley Fever is endemic, but return home to regions where doctors are unfamiliar with the disease.
Another problem is that about 5% to 10% of people exhibit serious symptoms of Valley Fever, with long-term lung problems, according to the U.S. Centers for Disease Control and Prevention (CDC). The infection can also spread from the lungs into the brain, spinal cord, or other parts of the body.