Federal health authorities have dramatically underestimated Valley Fever cases, with new data revealing the actual number may be 18 times higher than official reports, putting nearly 300,000 Americans at risk while government surveillance systems fail to capture the true scope of this potentially deadly disease.
Key Takeaways
- An estimated 273,000 symptomatic Valley Fever cases occurred in 2019, compared to officially reported numbers that were 10-18 times lower.
- The disease caused approximately 23,000 hospitalizations and 900 deaths in 2019, showing the significant public health impact.
- Arizona and California bear the heaviest burden, with an estimated 125,000 cases, yet government surveillance systems fail to properly track and report cases.
- Only 28 states and Washington DC currently report Valley Fever cases, creating dangerous gaps in monitoring this spreading disease.
- Environmental factors including drought and wildfires may be contributing to increased spread beyond traditional endemic regions.
Government Health Reporting System Fails to Capture True Valley Fever Crisis
New research released on June 3, 2025, reveals a shocking gap in our national disease surveillance system. The true burden of Valley Fever, a potentially deadly respiratory infection caused by inhaling Coccidioides fungal spores, is dramatically higher than government reports indicate. The study, published in JAMA Network Open, estimates that approximately 273,000 Americans suffered from symptomatic Valley Fever in 2019, with 23,000 hospitalizations and 900 deaths—numbers that dwarf official statistics by 10 to 18 times.
“Some of the main factors contributing to underreporting include underdiagnosis or misdiagnosis of coccidioidomycosis as bacterial or viral community-acquired pneumonia, coccidioidomycosis being reportable only in 28 states and Washington DC, and people who may not seek care for coccidioidomycosis even if they have symptoms,” said Mitsuru Toda, PhD.
Endemic States Bear the Heaviest Burden with Inadequate Response
The research reveals a national incidence rate of 83 cases per 100,000 people, but high-endemic states like Arizona and California face a much more severe situation with rates of 267 per 100,000 residents. These two states alone accounted for an estimated 125,000 cases in 2019. Despite the concentration of cases in these regions, surveillance and reporting systems remain woefully inadequate. The federal government’s failure to implement comprehensive nationwide reporting requirements has created dangerous blind spots in disease tracking.
“It is important for clinicians to test for coccidioidomycosis in patients with pneumonia who are not getting better on antibiotics, regardless of where they live,” said Mitsuru Toda, PhD.
Environmental Factors and Expanding Range Increase Public Health Threat
The study identified concerning trends that suggest Valley Fever’s impact may be growing beyond its traditional southwestern U.S. territory. Environmental factors, particularly drought conditions and wildfires that have intensified under current climate policies, appear to be contributing to the increased spread of the Coccidioides fungus. A recent surge in California cases in early 2025 highlights how changing environmental conditions may be expanding the geographic range of this pathogen, potentially putting more Americans at risk without their knowledge.
“Currently, only 28 states and Washington DC report coccidioidomycosis. Increasing the number of states that report coccidioidomycosis could help enhance our understanding of coccidioidomycosis epidemiology and the spread of Coccidioides species over time, especially in places where coccidioidomycosis is more common,” said Mitsuru Toda, PhD.
Critical Need for Better Testing and Public Awareness
The massive underreporting revealed in this study points to systemic failures in our healthcare approach to Valley Fever. Researchers emphasize that many cases are missed because doctors fail to test specifically for the fungal infection, instead misdiagnosing it as bacterial pneumonia. This leads to inappropriate antibiotic treatment while allowing the fungal infection to progress unchecked. The CDC’s delayed response to this growing health crisis has left citizens vulnerable, particularly in regions where the disease is becoming more prevalent.
“Increased awareness nationwide is needed among clinicians and the general public, as patients with knowledge of coccidioidomycosis may be more likely to be diagnosed earlier than those unfamiliar with the disease,” the authors stated.
The study, led by Samantha L. Williams, MPH, from the CDC, relied on data from the National Notifiable Diseases Surveillance System (NNDSS) and applied multipliers to account for significant underreporting. While the research has limitations, including reliance on data from only reportable states and use of expert opinion for some calculations, it provides the most comprehensive picture to date of Valley Fever’s true impact on American public health—an impact that has been systematically underestimated by government health authorities for years.
