Valley fever is a disease caused by a fungus that gets into your body through your lungs. It can make you feel like you have a cold or the flu and may cause a rash. Most people get better without treatment.
But if your body's natural defense system (immune system) is weak, valley fever can be deadly. In rare cases it can be deadly even for people with a normal immune system. Valley fever can spread from your lungs to other parts of your body. Those at higher risk for severe illness include pregnant women, people who have HIV infection, people who take medicines that weaken the immune system, and people who have diabetes. Filipinos, African Americans, Mexican Americans, and Native Americans also have a higher risk of dying from valley fever.1
Valley fever occurs mainly in dry desert areas of the southwestern United States, central California, and Mexico. It also occurs in dry areas of Central and South America.
Valley fever is also called desert fever, San Joaquin Valley fever, coccidioidomycosis, and desert rheumatism.
What causes valley fever?
You can get valley fever if you breathe in the fungus (Coccidioides immitis) that causes the disease.
The fungus grows in the soil. It gets into the air when the ground is broken and the dirt and dust spread into the air. People with jobs that require digging in the soil have the greatest chance of getting valley fever. This includes people who work on farms, in construction, and in archeology or paleontology. People who ride bikes or drive all-terrain vehicles (ATVs) in the desert also have a higher chance of getting it. Dust storms can spread the fungus into the air, so other people can also get valley fever.
Valley fever is not contagious. You cannot get it from another person or from animals.
After getting better, most people will not get valley fever again. This is called being immune. But valley fever can come back again in people who have weak immune systems and can't fight infection. This includes people who have HIV, are taking medicine that suppresses the immune system (such as prednisone or methotrexate), or have had an organ transplant.