Testing for Valley Fever

Key points

  • Healthcare providers can test your blood for Valley fever.
  • Skin tests are sometimes used to see if you have or ever had Valley fever.
  • If you are taking antibiotics for pneumonia and not getting better, ask your doctor about testing for fungal infections.
An illustration of a microscope

Testing

If you are being tested for Valley fever, your healthcare provider will collect a blood sample and send it to a laboratory. In a few days after receiving results, they should be able to tell you if you have Valley fever.

To learn more about your infection and treatment needs, your healthcare provider may also:

  • Do an imaging test, like an x-ray or CT scan, of your lungs.
  • Collect and test fluid from your respiratory tract or a biopsy

Skin tests

Your healthcare provider may do a skin test to see if you had Valley fever in the past or are currently infected. The test involves getting a small injection on the inside of your forearm, similar to a skin test for tuberculosis. If the test is positive, a bump will appear at the injection site. A healthcare provider must examine the injection site two days (48 hours) after the test was given to measure the size of the bump.

Skin test results

Positive test results – may mean that you have Valley fever or did in the past. The bumps show an immune response is happening. Many people test positive without ever having symptoms.

Negative test results- may mean you have not had Valley fever. Negative skin test results are not always accurate. People who are or were infected may get negative test results. Especially if they had a severe case of Valley fever or have a health condition or are taking a medication that interferes with results.

Talk to your healthcare provider

Valley fever has the same signs and symptoms as pneumonia caused by bacteria. If your healthcare provider does not run tests, they may start by treating you for bacterial pneumonia. They may prescribe an antibiotic and if you do not get better after antibiotic treatment, ask your doctor about testing for Valley fever or other fungal pneumonias. If you do not live in an area where Valley fever is spreading, be sure to tell your healthcare provider about any recent travel.

A healthcare provider talking to a patient
Ask your healthcare provider about the possibility of valley fever.