Extreme weather and airborne dust linked to rising Valley fever cases in El Paso

A new study by researchers at The University of Texas at El Paso has identified a significant rise in Valley fever cases in El Paso over the past decade and found strong connections between the disease and extreme weather, wind and airborne dust.

The study, published in the International Journal of Biometeorology, analyzed reported cases of coccidioidomycosis, commonly known as Valley fever, from 2013 to 2022. Researchers found that incidence rates more than tripled during that time.

Valley fever is caused by inhaling spores of a soil-dwelling fungus that become airborne under certain environmental conditions. While often mild, the disease can lead to serious respiratory illness and, in some cases, long-term complications and even death.

These results suggest that it's not just typical dusty conditions driving infections, but more intense and episodic environmental events. Extreme wind and dust events may disturb soils in ways that release larger amounts of the fungus into the air."

Thomas Gill, Ph.D., professor in the UTEP Department of Earth, Environmental and Resource Sciences, and co-author of the study

The research team used advanced statistical modeling to examine how weather patterns and air quality influence disease trends. Their findings show that higher disease incidence was associated with temperatures exceeding 102 degrees Fahrenheit in the prior month, peak wind gusts above 64 miles per hour several months earlier, and unusually high concentrations of dust particles in the air, particularly those that are 10 micrometers in diameter or smaller.

Although Valley fever is not contagious and is a reportable condition in El Paso County, researchers caution that the disease is likely underdiagnosed. Many cases present with symptoms similar to other illnesses such as influenza, pneumonia or even COVID-19, which can delay proper diagnosis and treatment.

Gabriel Ibarra-Mejia, M.D., Ph.D., associate professor of public health sciences and one of the lead researchers, emphasized the importance of these findings for public health planning.

"Our work shows that Valley fever risk can be anticipated based on environmental signals," Ibarra-Mejia said. "By recognizing the conditions that precede increases in cases, health officials and clinicians can be better prepared to detect, diagnose and respond to this disease."

The study also identified seasonal patterns, with the highest number of reported cases occurring in the summer months, particularly July and August.

"This research underscores the environmental factors in our region that contribute to breathing in Coccidioides fungus spores," said C. Scott Kruse, Ph.D., dean of the UTEP College of Health Sciences. "This includes air quality and climate-related risks that significantly impact public health, particularly in vulnerable communities."

El Paso's location in the Chihuahuan Desert, combined with frequent dust activity and increasing development, may further contribute to rising exposure risks, Ibarra-Mejia explained. He also noted that land disturbance from construction and urban expansion could also play a role in releasing fungal spores into the air.

The findings highlight the need for increased awareness among both the public and health care providers, especially during periods following extreme weather events, the researchers said.

"Understanding the connection between climate and disease is no longer optional," Gill said. "It's essential for building resilient communities in regions like ours."

Narges Khanjani, M.D., Ph.D., a professor of epidemiology and biostatistics in the Paul L. Foster School of Medicine at Texas Tech Health El Paso, was the co-lead author of the study, with additional contributions from researchers at New Mexico State University, the University of California, Merced and other institutions.