Valley Fever (or Coccidioidomycosis) is an infection caused by inhalation of spores of the fungus, Coccidioides, which lives naturally in the soil. It is highly endemic in Arizona and some areas of California, including San Luis Obispo County, Monterey County and the Central Valley region.
Although the fungus that causes Valley Fever can live anywhere in our county, many local cases are from the northern part of the county where conditions are especially dry and windy. When this soil is disturbed—by wind, construction, or other causes—people can breathe in the spores from this fungus and develop Valley Fever.
While many people do not experience symptoms of Valley Fever, it can cause serious complications for some people. More than 60 percent of people who become infected with Valley Fever do not experience any symptoms and do not need treatment. Around 30-40 percent of people develop sudden flu-like symptoms. Most of these people get well on their own within weeks. A small percentage—between one and five percent—will experience a much more serious form of the disease in which the infection spreads throughout the body. People who experience this serious form of Valley Fever are at risk of dying from complications of the disease and may need to take medication for the rest of their lives. Some people are more at risk for this serious form of the disease, including people with compromised immune systems (including people with HIV/AIDS, people currently on chemotherapy, women who are pregnant, and others) and people of African and Asian-Pacific descent.
For more information, see the San Luis Obispo County Valley Fever incidence map, view Public Health's report or pamphlet, or select any of the frequently asked questions below.