Ayomidamope Adebiyi, a board-certified family nurse practitioner at UC Merced's Occupational Health Services, is sounding an urgent call: Valley fever is being diagnosed far too late, and the cost to patients—and the healthcare system—is mounting.
A new study published in The Journal for Nurse Practitioners, led by Adebiyi following her Doctor of Nursing Practice from Johns Hopkins University, reveals a critical gap in how clinicians recognize and treat this fungal infection. While Valley fever was once seen as a regional concern confined to the southwestern United States, it is now spreading geographically and affecting far more people than official numbers suggest. Researchers estimate between 205,000 and 360,000 symptomatic cases occur annually—a figure dramatically higher than reported data, underscoring the scope of a disease that remains largely invisible to the medical system.
The problem is one of timing and recognition. Because Valley fever, or coccidioidomycosis, causes symptoms that mimic common respiratory illnesses—fatigue, cough, fever and shortness of breath—it is frequently overlooked in its early stages. The consequences are stark: eighty percent of people with Valley fever do not receive a correct diagnosis until a median of 23 days after their first clinical contact, if they are tested at all. Those weeks of illness compound into lost work days, unnecessary courses of antibiotics that fail to treat the underlying fungal infection, and in some cases, preventable complications.
"That's a lot of illness, a lot of days lost from work, and a lot of unnecessary antibiotics," Adebiyi explained, highlighting the human cost of delayed diagnosis that extends far beyond the individual patient.
The disease is expanding on multiple fronts. Climate patterns are playing a key role, with longer droughts followed by heavy rainfall disrupting soil and increasing the spread of airborne spores from the Coccidioides fungus. Simultaneously, expanding development in rural areas is raising exposure. "As rural areas are almost becoming semi-urban, there's more construction, which disrupts the soil," Adebiyi noted. Even improved reporting has made the disease more visible, yet many cases remain undiagnosed when symptoms are mild or resolve on their own.
At the heart of the study is the COCCI framework, a structured clinical guide designed to shift how providers approach Valley fever. Rather than the reactive "treat first, test later" model that has dominated practice, the framework directs clinicians to consider exposure history, order diagnostic testing early for persistent respiratory symptoms, identify patients at higher risk for severe disease—including immunocompromised individuals and those who are pregnant—check for serious complications such as neurologic involvement, and initiate appropriate care with reassessment. The framework provides a clear pathway from suspicion to diagnosis to management, removing guesswork from a disease that thrives on clinical uncertainty.
For endemic regions and areas where Valley fever may not be on clinicians' radar, the implications are significant. Better awareness, earlier testing and consistent clinical practices are not merely nice-to-have improvements—they are essential to reducing illness severity and preventing the unnecessary human and financial toll of delayed recognition. As Adebiyi's research makes clear, the path to better outcomes is not complicated. It begins with seeing Valley fever when it appears.