On Aug. 14, 2025, the California Department of Public Health (CDPH) is reminding California residents and visitors that Valley fever is common in parts of the state, particularly in the Central Valley and Central Coast. People experiencing long-lasting symptom​s like cough, fever, trouble breathing, chest pain, and tiredness – particularly people who have been around outdoor dirt or dust – should see a doctor or healthcare provider and ask about Valley fever.

Valley fever, also known as coccidioidomycosis or “cocci,” is caused by a fungus that grows in the soil and dirt in some areas of California. Valley fever is named after the San Joaquin Valley of California where it is most common. It can cause symptoms that look like COVID-19 or flu. Valley fever can also cause serious lung infections like pneumonia. People who live, work, go to school, or travel in areas where Valley fever is common are at risk of becoming sick. Although most people with Valley fever get better on their own and don’t need treatment, for some people it can become severe, chronic, or even fatal without care.  

As part of its mission to protect the health of all Californians, the CDPH is reminding California residents and visitors that Valley fever risk remains high in 2025. While Valley fever can occur at any time of the year, most people who get Valley fever breathe in the fungus in the late summer and fall and then get sick one to three weeks later. 

Valley fever is on the rise in California with over 5,500 provisional cases reported through the first six months of 2025. In 2024, California reported nearly 12,500 cases, the highest year on record for California and a significant jump from the 7,000-9,000 cases reported annually from 2017 through 2023. Rates of Valley fever continue to be highest in the southern San Joaquin Valley region of California, but cases have been increasing in other areas such as the northern Central Valley and the Central Coast.   

Research suggests the rise and spread of Valley fever may be linked to changes in climate. Wet winters after droughts help the fungus grow, and dry, windy weather in the following summer and fall can help the fungus get into the air. Increases in dirt-disturbing activities, like construction in high-risk areas, may also contribute to more Valley fever being reported.