Fungi that can make outdoor workers sick are now nationwide, researchers say

St. Louis — Workers in construction, landscaping, agriculture and other outdoor industries may be at risk of infections caused by soil fungi that historically had been found only in certain regions of the country, researchers at Washington University in St. Louis say.

The researchers examined 2007-2016 Medicare records for diagnoses of three types of fungal infections: histoplasmosis, coccidioidomycosis and blastomycosis. These infections occur when people breathe in spores from the soil. Work activities or even simply walking through soil can send the spores airborne.

“Fungal lung infections easily can be mistaken for bacterial or viral lung infections such as COVID-19, bacterial pneumonia and tuberculosis,” a WashU press release states. According to the researchers, the Centers for Disease Control and Prevention last revised its maps of disease-causing fungi in 1969. Since then, the fungi have spread to more areas.

“Every few weeks I get a call from a doctor in the Boston area – a different doctor every time – about a case they can’t solve,” said study author Andrej Spec, an associate professor of medicine at WashU and a specialist in fungal infections. “They always start by saying, ‘We don’t have [histoplasma] here, but it really kind of looks like histo.’ I say, ‘You guys call me all the time about this. You do have histo.’”

NIOSH published a webpage on histoplasmosis in December 2021.

WashU notes that many healthy adults and children “can fight off a fungal infection handily,” but older adults, infants and people with compromised immune systems can develop fever, cough, fatigue or other symptoms. Spec and his fellow researchers recommend that doctors and other clinicians place less reliance on regional exposure maps when looking at potential fungal infection symptoms.

The study was published online in the journal Clinical Infectious Diseases.