Valley Fever Coccidioidomycosis

Coccidioidomycosis, also known as Valley Fever, “San Joaquin Valley fever” or “desert rheumatism”, is a fungal infection that occurs when the spores that are the reproductive form of the fungus Coccidioides immitis enter the body through the lungs. Most of these infections (60%) develop little or no symptoms and heal completely without need for specific treatment. Rarely (less than 1%), the infection may spread from the lungs through the bloodstream to involve other organs. This form of Valley Fever is known as disseminated coccidioidomycosis and is a more severe disease. People over 60 years of age are at higher risk of developing a more serious form of this infection.

Anyone is susceptible to Valley Fever. Certain people are more likely to develop more severe forms of Valley Fever, including people who have weakened immune systems (such as those with HIV/AIDS, who have had an organ transplant, and who are taking medications like corticosteroids), pregnant women, people with diabetes, and people who are Black or Filipino. Recovery from Valley Fever generally leads to lifelong immunity.

Most infected people (60%) do not show any symptoms. Of those that do, most develop flu-like symptoms that usually go away on their own after a few weeks. These symptoms include fatigue, cough, fever, shortness of breath, headache, night sweats, muscle and joint aches, and rash on upper body or legs. The spores can also enter through a cut or wound and cause a skin infection, but this only occurs in extremely rare cases.

A small percentage of people develop a more severe form of Valley Fever. In approximately 5 to 10% of people, the infection can cause serious and long-term lung problems. In about 1% of people, the infection spreads to other parts of the body, such as the central nervous system (brain and spinal cord), skin, or bones and joints.

In most people with Valley Fever, the symptoms are not severe and will go away within a few weeks without the need for treatment. Some healthcare providers may prescribe antifungal medication to reduce symptoms or prevent them from getting worse, particularly for people who are at high risk of developing a more severe infection.

The Coccidioides fungi live in the dust and soil in some areas in the southwestern United States, Mexico, and Central and South America. In the United States, the fungi live in Arizona, California, Nevada, New Mexico, Texas, and Utah. It was also recently found in south-central Washington State.