- Coccidioidomycosis an infection of the lungs and skin characterized by excessive sputum and nodules.
- Many people who are exposed to the fungus Coccidioides never have symptoms.
- Other people may have flu-like symptoms that go usually away on their own after weeks to months.
The term “Valley fever” usually refers to Coccidioides infection in the lungs, but the infection can spread to other parts of the body in severe cases (this is called “disseminated coccidioidomycosis”).
- The fungus is known to live in the soil in the southwestern United States and parts of Mexico and Central and South America.
- People can get Valley fever by breathing in the microscopic fungal spores from the air in these areas.
- Most people who breathe in the spores don’t get sick, but some people do.
- Usually, people who get sick with Valley fever will get better on their own within weeks to months, but some people will need antifungal medication.
- Certain groups of people are at higher risk for developing the severe forms of the infection, and these people typically need antifungal treatment.
- It’s difficult to prevent exposure to Coccidioides in areas where it’s common in the environment, but people who are at higher risk for severe Valley fever should try to avoid breathing in large amounts of dust if they’re in these areas.
Skin lesions due to Coccidioides immitis
Rash (erythema nodosum) due to Valley fever
Symptoms of Valley fever include:
- Fatigue (tiredness)
- Shortness of breath
- Night sweats
- Muscle aches or joint pain
- Rash on upper body or legs
In extremely rare cases, the fungal spores can enter the skin through a cut, wound, or splinter and cause a skin infection.
Symptoms of Valley fever may appear between 1 and 3 weeks after a person breathes in the fungal spores.
Duration of symptoms
The symptoms of Valley fever usually last for a few weeks to a few months. However, some patients have symptoms that last longer than this, especially if the infection becomes severe.
Severe Valley fever
Approximately 5 to 10% of people who get Valley fever will develop serious or long-term problems in their lungs. In an even smaller percent of people (about 1%), the infection spreads from the lungs to other parts of the body, such as the central nervous system (brain and spinal cord), skin, or bones and joints.
People in endemic areas, particularly those who have occupations or participate in activities exposing them to dust (e.g., construction or agricultural workers, archaeologists, and military trainees). Risk factors for severe or disseminated coccidioidomycosis include African-American race 14 or Filipino ethnicity, HIV/AIDS, use of immunosuppressive medications, 17 organ transplant, 18 diabetes mellitus, or pregnancy.
Serologic tests to detect IgM and IgG antibodies are most often used to diagnose coccidioidomycosis. Other methods include culture and microscopy.
- Enzyme immunoassay (EIA): A very sensitive and commonly used method for diagnosing coccidioidomycosis.. Two EIAs for detection of specific IgM and IgG antibodies against Coccidioides are currently available:
- Premier ® Coccidioides EIA – Meridian Bioscience, Inc.
- Enzyme Immunoassay for detection of specific antibodies against Coccidioides spp – Immuno Mycologics, Inc. (IMMY)
- Immunodiffusion (ID): detects IgM antibodies; positive early in the course of infection.
- Complement Fixation (CF): detects IgG antibodies and allows for assessment of disease severity.
- Lateral Flow Assay (LFA): The Sona Coccidioides Antibody LFA (Immuno Mycologics, Inc. [IMMY]) is a rapid test (~30 minutes) to detect the presence of total antibodies against Coccidioides spp (IgM or IgG).
- Culture: Can be performed on tissue and respiratory specimens; however, sputum can be difficult to obtain for culture since patients’ coughs are often non-productive. Processing and manipulation of cultures should be done in a biosafety level 3 laboratory.
- Microscopy: for detection of spherules in tissue or respiratory secretions; low sensitivity.
- Urinary antigen detection: Not widely used, but may have some utility in diagnosing coccidioidomycosis in immunocompromised patients with severe forms of the disease.
- Polymerase Chain Reaction (PCR): A PCR for detection of Coccidioides directly from lower respiratory specimens (GeneSTAT.MDx Coccidioides – DxNA, LLC) has been approved by the Food and Drug Administration. Other PCR tests are still experimental but appear promising.
No evidence from randomized trials exists to determine whether antifungal treatment for uncomplicated coccidioidal infections reduces symptom duration or prevents complications. Some infections will resolve without antifungal treatment. Infectious Diseases Society of America (IDSA) guidelines suggest treatment for primary pulmonary coccidioidomycosis in patients who:
- Are immunosuppressed
- Have severe or significantly debilitating illness
- Have diabetes or are frail because of age or comorbidities
- Are pregnant
- Are of African or Filipino ancestry
In persons who develop progressive, chronic, or disseminated disease, symptoms may persist for months or even longer. Meningitis can lead to permanent neurologic damage. Mortality is high in HIV-infected persons with diffuse lung disease.
Anyone who lives in or travels to the southwestern United States (Arizona, California, Nevada, New Mexico, Texas, or Utah), or parts of Mexico or Central or South America can get Valley fever. Valley fever can affect people of any age, but it’s most common in adults aged 60 and older. Certain groups of people may be at higher risk for developing the severe forms of Valley fever as noted below.
People who have weakened immune systems, such as:
- Have HIV/AIDS
- Have had an organ transplant
- Are taking medications such as corticosteroids or TNF-inhibitors
- Pregnant women
- People who have diabetes
- People who are Black or Filipino
It’s very difficult to avoid breathing in the fungus Coccidioides in areas where it’s common in the environment.
- Try to avoid areas with a lot of dust like construction or excavation sites. If you can’t avoid these areas, wear an N95 respirator (a type of face mask) while you’re there. Click for more information about respirators.
- Stay inside during dust storms and close your windows.
- Avoid activities that involve close contact to dirt or dust, including yard work, gardening, and digging.
- Use air filtration measures indoors.
- Clean skin injuries well with soap and water to reduce the chances of developing a skin infection, especially if the wound was exposed to dirt or dust.
- Take preventive antifungal medication if your healthcare provider says you need it.