New Mexicans likely among the most at-risk populations for Valley fever

The first comprehensive study of Valley fever in New Mexico found that people in the state are likely among the most at-risk populations for the disease in the United States.

“We’ve known anecdotally for more than 80 years that Valley fever exists in New Mexico,” said Morgan Gorris, a Los Alamos National Laboratory scientist and corresponding author on the paper in the journal Pathogens. “But this is the first study to look at all the data — including reported cases, soil samples and rodent samples — to tell us that, yes, Valley fever is endemic to New Mexico.”

Valley fever (coccidioidomycosis) is a disease commonly associated with exposure to dust because people contact the disease when they inhale soil-dwelling fungi that infect the lungs. While most cases are minor, the disease can be severe and even fatal, especially among older populations.

The research team — a collaboration among scientists at Los Alamos National Laboratory, the New Mexico Department of Health, the University of New Mexico, New Mexico State University and New Mexico Tech — analyzed more than 1,500 human cases over 18 years.

On average, 86 cases were reported each year in the state, with the highest levels of incidence in northwestern and southwestern New Mexico. Additionally, the team analyzed 300 soil samples near Las Cruces and reported the first known positive soil samples collected from the state; the majority of which were from dry, grassland-dominated sites and rodent burrows.

“Dry, dustier parts of the state seem to be most at risk for Valley fever. These areas are also prone to dust storms, which could expose people to the fungus,” Gorris said. “Rodent burrows may have higher levels of the pathogen since rodents, too, can get sick with this disease.”

The team also tested a selection of rodents from museum collections over the past 27 years and found rodents positive for the fungus from Catron, Doña Ana, Sierra and Socorro counties — although they stressed that the fungus could be present in other areas, as well.

The research team hopes this paper will shed more light on the prevalence of the disease in New Mexico among doctors, epidemiologists and the general population.

“A lot of people don’t know what Valley fever is; they’ve never heard of it,” Gorris said. “It’s important that people are aware of the disease so they can seek early treatment if they suspect an infection.”

The research was funded by Los Alamos’ Laboratory Directed Research and Development program.

“As a national security laboratory, we’re interested in how, where and why diseases spread,” Gorris said. “Biosecurity is an important component of national security. Understanding where different diseases exist is important to protect people who live and work there, and to protect our warfighters who might be exposed to unusual pathogens.” 

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Paper: “The Epidemiology of Coccidioidomycosis (Valley fever) and the Disease Ecology of Coccidioides spp. in New Mexico (2006–2023).” Pathogens.

DOI: 10.3390/pathogens14060607

Funding: Laboratory Directed Research and Development Program

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