Scientists say people get sick from drug-resistant mold

Mold growth

 

Scientists say people get sick from drug-resistant mold found in flowerbeds and compost bins

Scientists found a link between drug-resistant fungi in the environment and human lungs. It causes lung infections in people with weakened immune systems.

Some types of mold have developed drug resistance from agricultural exposure, which makes treating fungal infections more difficult.

Researchers have confirmed that drug-resistant mold infections in gardens, homes, and farms cause life-threatening, chronic diseases.

Molds like Aspergillus fumigatus are ubiquitous worldwide, so the average person's immune system is adept at recognizing and eliminating inhaled mold spores. The hefty dose of fungicide will kill molds like Aspergillus; gradual exposure in the environment can lead to drug resistance, Imperial genetic epidemiology fellow Joanna Rhodes told Insider.

"It's like gradually building a tan," said Rhodes, its lead author. "If it's exposed a little bit at a time, it will slowly develop resistance."

This study is one of the first to confirm that people can contract drug-resistant fungal infections from their everyday environments.

To question the connection, Rhodes and her team collected and analyzed more than 100 Aspergillus samples from infected patients across England, Wales, Scotland, and Ireland between 2005 and 2017. They also sequenced mold samples from these patients' environments and compared them to matches.

For some patients, Aspergillus samples taken from the lungs were nearly identical to spores found in nearby soil or other environmental sources, selected based on hospital location. In six cases, drug-resistant aspergillosis infection could be traced back to the patient's environment with high confidence.

Fungi are evolving drug resistance

Researchers like Rhodes are particularly interested in tracking drug-resistant strains of mold, which are on the rise worldwide.

According to estimates cited in the study, natural Aspergillus infections infect 10 to 20 million people worldwide. Conditions are usually treated with antifungal drugs called azoles, but emerging drug resistance poses a growing threat.

Nearly half of the samples collected in the UK study were resistant to at least one antifungal drug, and more than 10% of the samples (including three patients) developed resistance to two or more azoles.

Although drug resistance can emerge during hospitalization, the authors concluded that the fungi in question developed resistance before infiltrating any human lungs, indicating agricultural fungicides.

Antifungal resistance can be fatal to patients with compromised immune systems, whether taking immunosuppressive medications or treating an autoimmune condition. Studies have found a 25% increase in mortality three months after infection with drug-resistant aspergillosis compared to those with a typical treatable fungal infection.

How to avoid inhaling mold in your home and garden?

Like many fungi, Aspergillus thrives in decomposing environments. Soil bottoms, compost containers, and decaying wood are all well suited for the growth of fungi, and mold spores can spread in the air and spread to new environments.

Rhodes said that drug-resistant Aspergillus is nearly ubiquitous because spores can move through the air and pass genetic material to wild Aspergillus colonies that have never encountered azoles.

Because the risk of exposure is so widespread, the authors call for better monitoring of drug-resistant strains of fungi.

While the average person cannot sequence mold spores from their backyard, Rhodes recommended leaving windows open to prevent aspergillus buildup in the home and remove other pathogens such as the coronavirus. N95 face masks obtained during the COVID-19 pandemic can also avoid inhaling spores while gardening or handling manure.