Fungal outbreak at Mich. paper mill kills 1, sickens nearly 100
At least one person has died and nearly 100 people have gotten sick in a rare fungal outbreak at a paper mill in Michigan, health authorities said, prompting the plant to temporarily close as local and federal investigators try to identify the source.
The outbreak of blastomycosis at the Billerud paper mill in Escanaba, Mich., has escalated since February.
Local health authorities initially identified about 15 likely cases. By mid-April, that number had grown to 21 confirmed cases and 76 probable cases. Twelve people have been hospitalized and one person has died.
All of the reported cases have been among workers, contractors, or visitors to the plant.
Billerud, a Sweden-based paper and packaging company, said on Thursday it planned to close the mill for three weeks starting next week to conduct a deep clean, inspect ventilation systems, replace filters, and test various raw materials coming into the mill, which employs about 830 people. The additional cleaning requires large portions of the mill to be empty, it said.
“Identifying the source can be difficult because the Blastomyces fungus is endemic to the area,” the company said in a statement. “There has never been an industrial outbreak of this nature documented anywhere in the US.”
Blastomycosis is an infection associated with the Blastomyces fungus, which grows in moist soil and decomposing matter, such as wood and leaves, and can become airborne if disturbed.
Blastomycosis infections are rare. In 2019, the US Centers for Disease Control and Prevention reported 240 cases of blastomycosis in total.
On average over the past five years, only 26 cases have been reported in all of Michigan, according to the local health agency.
However, the agency noted, the Upper Peninsula of Michigan is a known risk area for blastomycosis infection.
According to the CDC, “Blastomycosis remains poorly understood.” The fungus mainly lives in Midwestern, South Central, and Southeastern states, especially in areas around the Ohio and Mississippi River valleys, the Great Lakes, and the St. Lawrence River.
Most people who breathe in Blastomyces spores will not get sick. Symptoms include a cough (sometimes with blood), fever, chest pain, difficulty breathing, night sweats, fatigue, weight loss, muscle aches, and joint pain. Symptoms appear between three weeks to three months after exposure. Blastomycosis can be treated with antifungal medications.
Symptoms for the initial patients began in January and February, authorities said.
A team led by the National Institute for Occupational Safety and Health visited the mill on March 27 and 28 after a request from Billerud, according to an April 7 letter from Marcia Stanton, a health scientist with the agency, which was posted by CBS.
The agency advised the company to make N95 masks available to reduce potential exposure and to inspect the ventilation system and ductwork for “evidence of water incursion and microbial growth” while investigations continued.
On Saturday, the CDC said in a statement that it planned to return to the mill in late April to offer Blastomyces urine antigen screening tests for potential exposure.