Optimized, efficient answers

Streamlined, patient-focused testing

Valley fever, or coccidioidomycosis, is an infection caused by the coccidioides fungus. Present in the arid soils of the southwestern United States and parts of Mexico, Central America, and South America, coccidioides spores can be inhaled by humans. While most individuals with coccidioides infection do not exhibit symptoms, certain individuals, such as those who are immunocompromised, are at higher risk for becoming severely ill.

Confirming a valley fever diagnosis typically requires a multi-pronged approach that uses both serologic (e.g., polymerase chain reaction [PCR]), and molecular testing. This approach has numerous challenges.

  • Delayed serology test results of up to 72 hours for all patients.
  • Inability of certain patients to tolerate invasive specimen collection procedures.
  • Variable results depending on specimen type.

Enhanced test utilization through an algorithmic testing approach

Mayo Clinic Laboratories employs an alternative testing approach. Our streamlined, reflexive coccidioides evaluation first uses molecular testing to screen patients’ blood for coccidioides antibodies using a highly sensitive, automated enzyme immunoassay (EIA), which can detect the species directly from clinical specimens.

If positive, testing cascades to serologic testing (e.g., complement fixation [CF] with immunodiffusion [ID]), to confirm diagnosis. If screening is negative, results are quickly reported, providing patients with clinical information to assist in care.

Key testing

COXIS | Coccidioides Antibody Screen with Reflex, Serum*

  • Uses EIA to screen for coccidioides antibodies with a reflex to complement fixation/immunodiffusion if results are reactive (positive).
  • Offers increased sensitivity (EIA) and specificity (CF/ID) for diagnostic certainty.
  • Negative results reported in 24 hours.
  • Lower testing costs when only using EIA.
  • Support testing stewardship through improved test utilization.

*If positive, will reflex to:

By the numbers


cases of valley fever reported to the Centers for Disease Control and Prevention in 2019


of individuals with coccidioidomycosis are asymptomatic


annual deaths associated with coccidioidomycosis

Additional testing

Learn how to order these evaluations at your institution.


  1. Valley Fever (Coccidiomycosis) Awareness. Fungal Diseases. Centers for Disease Control and Prevention. https://www.cdc.gov/fungal/features/valley-fever.html. Page reviewed August 2022. Accessed January 2023.
  2. Valley Fever (Coccidiomycosis) Statistics. Fungal Diseases. Centers for Disease Control and Prevention. https://www.cdc/fungal/diseases/coccidioidomycosis/statistics/html. Page reviewed July 2022. Accessed January 2023.
  3. Laniado-Laborín R. Coccidioidomycosis and other endemic mycoses in Mexico. Rev Iberoam Micol. 2007;24(4):249-258. doi:10.1016/s1130-1406(07)70051-7