Coccidioidomycosis and COVID-19 Co-Infection, United States, 2020

Alexandra K. Heaney; Jennifer R. Head; Kelly Broen; Karen Click; John Taylor; John R. Balmes; Jon Zelner; Justin V. Remais


Emerging Infectious Diseases. 2021;27(5):1266-1273. 

In This Article

Co-circulation With SARS-CoV-2 Hampering Coccidioidomycosis Diagnosis

The diagnosis of coccidioidomycosis in areas with community transmission of COVID-19 might be challenging because the diseases cause similar symptoms, which might exacerbate existing delays in coccidioidomycosis diagnosis and treatment. Without antifungal treatment, coccidioidomycosis patients are at risk for severe illness, including disseminated disease, and for death.[45] Promptly administering of antifungal treatments reduces unnecessary use of antimicrobial drugs and resolves symptoms more effectively.[45] In addition, early case management, including assessing of risk factors for severity, regular follow-up visits to monitor symptoms, regular testing to check antibody titer levels, and physical therapy, is crucial to mitigating severe disease.[46]

One reason for the underdiagnosis of coccidioidomycosis is low testing rates. For instance, a study in Tucson, Arizona, estimated that 15%–44% of community-acquired pneumonia cases could be attributed to coccidioidomycosis,[47] but only 2%–13% of community-acquired pneumonia cases were tested for coccidioidomycosis.[48] Valdivia et al.[47] found that half of patients had ≥2 clinic visits before being tested for coccidioidomycosis. Low sensitivities of coccidioidomycosis tests might further contribute to delays in diagnosis (Appendix). Given such diagnostic constraints, the median time between seeking healthcare and coccidioidomycosis diagnosis was estimated to be 23 days in Arizona.[49]

The COVID-19 pandemic might contribute to further delays in coccidioidomycosis diagnosis. Both diseases can cause dry cough, muscle aches, headache, fatigue, and difficulty breathing; however, patients with COVID-19 tend to have a more acute progression of symptoms than those with coccidioidomycosis (;[50] Appendix references 51–54). Although pulmonary specialists and primary care physicians in regions to which coccidioidomycosis is endemic are probably aware of the diagnosis and treatment of this fungal infection, physicians in other regions might be less familiar with the diagnosis. Attributing coccidioidomycosis symptoms to COVID-19, whether presumed or laboratory-confirmed, might preclude coccidioidomycosis diagnosis in patients with monoinfections or co-infections. In addition, underutilization of healthcare services during the COVID-19 pandemic might result in further delays in the testing and diagnosis of coccidioidomycosis (Appendix reference 55).