Valley Fever

Valley Fever is on the Rise

In California, the number of reported Valley fever cases has greatly increased in recent years. Since 2000, Valley fever cases increased from less than 1,000 cases to more than 9,000 cases in 2019. In 2024, California reported nearly 12,500 cases, the highest number on record for California.

To see recent data, view CDPH Valley Fever Data and Publications

People who work or dig outdoors in certain areas of California are at greater risk of getting Valley fever, including wildland firefighters digging and moving soil to control fires during fire season. Fire safety crews and other outdoor workers in California should learn about Valley fever and know the symptoms, which sometimes appear weeks after exposure to dust outdoors.

Learn more: Groups at Risk | Symptoms | Resources for Outdoor Workers & Employers

What is Valley fever?

Valley fever (also called coccidioidomycosis or “cocci”) is a disease caused by a fungus that grows in the soil and dirt in some areas of California and the southwestern United States. People and animals can get sick when they breathe in dust that contains the Valley fever fungus. This fungus usually infects the lungs and can cause respiratory symptoms including cough, fever, chest pain, and tiredness or exhaustion.

Valley fever transmission: The Valley fever fungus grows in dirt and soil, but is too small to see; fungus spores get in the air when dust is stirred up by the wind or by digging; people an animals breathe in the spores from dust in the air; the fungus usually infects the lungs, but it can spread to other organs.

Most cases of Valley fever in California are reported from the Central Valley and Central Coast regions. But Valley fever cases have also been increasing outside of these regions as California experiences more drought. Valley fever cases are on the rise in California, including in the northern Central Valley and southern coastal areas of California. Learn more about where Valley fever is common and how drought impacts Valley fever in California.