Valley fever cases have continued to increase in California, with 2025 showing high case counts following a record year in 2024. The California Department of Public Health (CDPH) is urging residents, visitors, and healthcare providers to remain vigilant as the illness remains prevalent, especially in the Central Valley and Central Coast regions.
Valley fever, also known as coccidioidomycosis or “cocci,” is caused by a fungus that lives in soil and dirt in certain areas of California. People can contract the disease by breathing in fungal spores from dust outdoors. Symptoms may include cough, fever, trouble breathing, chest pain, and tiredness—symptoms that can resemble COVID-19 or the flu. While most people recover without treatment, some cases can become severe or even fatal.
“California had a record year for Valley fever in 2024 and, so far, case counts are high in 2025. Valley fever is a serious illness that’s here to stay in California. We want to remind Californians, travelers to California, and their healthcare providers to watch for signs and symptoms of Valley fever to help detect it early,” said CDPH Director and State Public Health Officer Dr. Erica Pan. “If you have been sick with symptoms like cough, fever, trouble breathing, and tiredness for more than 7 to 10 days, please talk to a healthcare provider about Valley fever, especially if you’ve been outdoors in dusty air in the Central Valley or Central Coast regions.”
Provisional data shows over 5,500 cases reported during the first half of 2025. In comparison, nearly 12,500 cases were reported statewide during 2024—the highest on record—up significantly from annual totals between 7,000 and 9,000 from 2017 through 2023. Rates remain highest in the southern San Joaquin Valley but are rising elsewhere including the northern Central Valley and Central Coast.
Experts suggest climate patterns may be contributing to this trend. Wet winters followed by dry summers can support fungal growth then spread spores via wind-blown dust later in the year. Increases in activities that disturb soil—such as construction—may also play a role.
People who live or spend time where Valley fever is common are advised to take precautions when conditions are windy or dusty: staying indoors with windows closed; keeping car windows up when driving; wetting down soil before digging; or wearing an N95 mask if outdoor exposure cannot be avoided.
Diagnosis can be challenging since symptoms mimic other respiratory illnesses. Healthcare providers rely on blood tests or other laboratory methods for confirmation. Those at greater risk of severe illness include older adults (over age 60), individuals with diabetes or weakened immune systems, pregnant women—and studies show Black and Filipino people may also face higher risk due to various factors.
Patients experiencing persistent respiratory symptoms after being exposed to dust should seek medical advice regarding possible Valley fever infection.
Further information is available on CDPH’s Valley Fever website, which provides resources for both the public and healthcare professionals including updated diagnostic guidelines.
