A deadly fungus that kills up to one in five people it infects may be more common than previously thought, a study suggests.
People contract the fungus behind blastomycosis by breathing in spores released by rotting wood or leaf litter, which can then take root in the lungs and spread to the skin, brain and spinal cord, causing fatal pneumonia and inflammation.
Officials have previously suggested that the disease is not common and only tracked infection in five states, primarily in the Midwest.
But researchers at the Centers for Disease Control and Prevention (CDC) now suggest otherwise, after finding that the fungus was more common in Vermont than in four of the five states where it is tracked.
The map above shows states where cases of blastomycosis have been confirmed (red), recently confirmed (orange), or suspected (blue).
An examination of tens of thousands of health insurance claims showed the disease had a rate of 1.8 cases per 100,000 people in Vermont between 2011 and 2018.
But in 2019 and 2020, this figure increased to three cases per 100,000.
For comparison, in four of the states monitored (Arkansas, Louisiana, Michigan and Minnesota) the rate did not exceed one per 100,000 in the same period.
It was only higher in Wisconsin, where the average was about three per 100,000.
The researchers wrote in the paper: “Our findings… align with a growing body of evidence suggesting that the burden of endemic blastomycosis is greater than commonly appreciated.”
“These results challenge common assumptions about the epidemiology and ecology of this disease and reflect the need for future studies.”
They added: “Physicians should consider blastomycosis in patients with compatible signs and symptoms.”
Blastomycosis is a disease caused by the Blastomyces fungus, which can lurk around waterways and in moist soil and leaf litter.
Patients infected with the fungus may suffer from a mild to moderate infection that causes cough, fever and chills.
Sonya Cruz, 31, mother of one, from Wisconsin, photographed with her husband John Cruz on their wedding day in 2019. She died of blastomycosis last year.
Blastomycosis (file image of Blastomyces fungus) can trigger cold-like symptoms in the early stages, but the fungus can then spread to other areas of the body and cause more serious illness.
But in severe cases, they can progress within days or weeks to pneumonia, skin lesions (which appear as lumps, blisters, or ulcers), and neurological problems (warning signs of encephalitis, or inflammation of the brain).
This happens because the fungus can spread through the body through the bloodstream or lymphatic system and begin to wreak havoc in other areas.
Infections are diagnosed by a blood or urine test and can be treated by giving antifungal medications such as itraconazole, which is brand name Sporanox.
In addition to the five states that reported the illness, cases have also been previously confirmed in Illinois, Missouri and Mississippi.
But all of these states are located around the Mississippi River basin, making the detection of the fungus in Vermont an outlier.
Last year, more than a hundred people were sickened by the fungus at a paper mill in Michigan — the largest outbreak in U.S. history. Thirteen people were hospitalized and one died.
A mother of one in Wisconsin also died from a fungal infection after doctors initially missed the infection and sent her home with antibiotics.
Sonya Cruz, 31, suffered respiratory failure shortly before her death and had to be put on a ventilator and sedated.
Her husband John said at the time: ‘They took away my taste. I’m not saying the hospital or whatever. Whatever it was, he took my wife.
Vermont claims data showed that 116 people had been diagnosed with the infection between 2011 and 2020.
Of the patients, 34 were hospitalized and four were also reported to have died from the disease.
Across Vermont, three of its counties in the north-central area (Lamoille, Orleans and Washington) reported the most cases.
The researchers used the Vermont Uniform Health Care Assessment and Reporting System, which covers about 75 percent of the state’s residents, to collect the data.
Insurance claims were checked for diagnosis codes 116.0 or B40.X, which indicate a plastomycosis infection.
Most of the patients were men (about 60 percent) and had an average age of about 55 years.