Valley fever cases in California have continued to rise in 2025, following a record high reported in 2024, according to the California Department of Public Health (CDPH). The department is urging residents, visitors, and healthcare providers to remain alert for symptoms of the illness during Valley Fever Awareness Month.
Valley fever, or coccidioidomycosis, is caused by a fungus found in soil and dirt in certain areas of California. It is most common in the San Joaquin Valley but can also be found along the Central Coast and other regions. The illness often presents with symptoms similar to COVID-19 or influenza and can lead to serious lung infections such as pneumonia. People who live, work, go to school, or travel through affected areas are at risk.
“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.”
Through the first six months of 2025 alone, over 5,500 provisional cases have been reported statewide. In 2024 nearly 12,500 cases were recorded—marking the highest annual total on record for California and representing a significant increase from previous years when annual case numbers ranged between 7,000 and 9,000 from 2017 through 2023. The southern San Joaquin Valley continues to report the highest rates; however cases are also increasing elsewhere including the northern Central Valley and Central Coast.
Research indicates that changing climate patterns may be contributing to this trend. Wet winters followed by droughts allow the fungus responsible for Valley fever to grow more readily; subsequent dry and windy conditions help spread fungal spores into the air. Additionally, increased construction activity that disturbs soil may further elevate exposure risks.
People can contract Valley fever by inhaling dust containing fungal spores while outdoors; pets are also susceptible but person-to-person transmission does not occur. To reduce risk of infection CDPH recommends staying indoors with windows closed during windy or dusty conditions; keeping car windows shut while driving through affected areas; wetting down soil before digging; and considering use of N95 respirators when outdoor exposure cannot be avoided.
The disease can be difficult both to prevent and diagnose because its symptoms resemble those of other respiratory illnesses. Individuals experiencing persistent coughs or fevers after spending time outdoors—especially those involved in construction work or wildland firefighting—are encouraged to consult their healthcare provider about possible infection.
While anyone can develop severe forms of Valley fever requiring hospitalization—and sometimes resulting in lifelong health effects—certain groups face higher risks: older adults over age sixty; people with diabetes or weakened immune systems; pregnant individuals; as well as Black or Filipino populations due possibly both to underlying health disparities and genetic factors.
Diagnosis typically involves blood tests or laboratory analysis conducted by medical professionals who determine whether treatment is necessary based on severity of illness.
More information about prevention strategies and clinical guidelines is available on CDPH’s Valley Fever website as well as resources specifically designed for healthcare providers seeking up-to-date diagnostic algorithms from organizations such as CDC.
