Valley Fever Information for Healthcare Providers
If you suspect coccidioidomycosis or have a case of coccidioidomycosis you would like to discuss, experts are available to consult at the Valley Fever Center for Excellence.
Coccidioidomycosis is almost always caused by inhalation of the Coccidioides fungi found naturally in the environment. The fungus is found in the soil throughout the southwestern United States (Arizona, California, Nevada, New Mexico, Texas, and Utah) and in Central and South America. Coccidioides has also been found in other parts of the United States including south-central Washington.
The incubation period is 1-4 weeks; however, most individuals with coccidioidomycosis are asymptomatic. Only 40% of individuals with coccidioidomycosis experience symptoms. No specific signs or symptoms of coccidioidomycosis are pathognomonic and the disease can often resemble influenza, COVID-19, acute bronchitis, or pneumonia. Coccidioidomycosis is also a common cause of community-acquired pneumonia (CAP) in highly endemic regions.
Some individuals with coccidioidomycosis may have dermatologic or rheumatologic complaints. Coccidioidomycosis should be considered if an individual traveled to an endemic region within 1-2 months of developing CAP, dermatologic, or rheumatologic signs and symptoms.
In rare instances, coccidioidomycosis disseminates from the lungs to other tissues, most commonly the skin, but may also disseminate to bones, joints, and meninges.
Most infections are identified using serologic tests which are available at clinical laboratories. Enzyme immunoassays (EIAs) are the most common tests used for initial screening for coccidioidal infection. Typically, a positive EIA test is confirmed with immunodiffusion tests, which are more specific. These detect serum IgM (tube precipitin IMDF) and IgG (complement-fixation (CF) antibodies.
Any positive test result indicates an active or current infection, including IgG antibody tests. An individual with an EIA IgG positive test likely has an active or current infection. This is an unusual interpretation of an IgG test; however, once the infection resolves, most tests revert to negative.
Treatment is not needed for every coccidioidomycosis infection. When treatment is indicated, antifungal drugs should be used. Antifungal treatment is recommended for severe cases of coccidioidomycosis or for disseminated coccidioidomycosis.
- Information for Healthcare Professionals about Valley Fever (Coccidioidomycosis)
- 2016 Infectious Disease Society of America Clinical Practice Guideline for the Treatment of Coccidioidomycosis
- Provider Page (Arizona Department of Health Services)
- Provider Page (Centers for Disease Control and Prevention)
- Valley fever Data Page (Arizona Department of Health Services)