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Valley Fever

Valley fever is on the rise in California. Learn what it is. Learn the symptoms. Learn how to help prevent it.

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.

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.

Valley Fever is on the Rise

In California, the number of reported Valley fever cases has greatly increased in recent years. In fact, Valley fever cases tripled from 2014–2018, and from 2018–2022, between 7,000 and 9,000 cases were reported each year.






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 how drought impacts Valley fever in California.

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