Blastomycosis outbreak sickens workers at paper mill in Upper Peninsula

Blastomyces dermatitidis organism taken through a microscope at 100x from a skin sore on a...
Blastomyces dermatitidis organism taken through a microscope at 100x from a skin sore on a Great Dane suffering from blastomycosis(Wikimedia Commons)
Published: Apr. 11, 2023 at 2:36 PM CDT
Email This Link
Share on Pinterest
Share on LinkedIn

ESCANABA, Mich. (WBAY) - Public health officials say nearly 100 paper mill workers in Michigan’s Upper Peninsula may be affected by an outbreak of blastomycosis.

The infection is caused by breathing spores from a fungus that’s often found in decomposing matter, such as wood.

Public Health of Delta and Menominee Counties says there are 19 confirmed cases associated with the Billerud Paper Mill and 74 “probable” cases.

“The health and safety of our Escanaba employees is our first priority,” Brian Peterson, operations vice president for the mill, wrote in a statement.

Billerud requested a health hazard evaluation at its site last month. As of late March, Peterson said no causal link was found between the outbreak and the mill.

“Although the source of the infection has not been established, we continue to take this matter very seriously and are following recommendations from health and government officials and implementing numerous, proactive steps to protect the health and safety of our employees, contractors and visitors,” Peterson wrote.

Peterson said the company is receiving guidance from the local health department, the Michigan Department of Health and Human Services, the federal agencies including the Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health. It’s taken measures including extensive cleaning of common areas, inspections of ventilation systems, testing of raw materials coming into the mill, and providing N95 masks to all employees with instructions on how to wear them properly.

The health department learned about 15 possible cases in late February. Some of the patients said symptoms started the month before.

It says blastomycosis infections are “exceedingly rare” -- there were an average of 26 cases a year in the entire state of Michigan over the past 5 years.

Blastomycosis can cause coughing (sometimes with blood), difficulty breathing, fever, chest pain, night sweats, fatigue, weight loss, muscle aches and joint pain. Anyone with these symptoms is urged to contact their health care provider and discuss whether they should be tested for blastomycosis. According to U.W. Health, the fungal spores colonize in the lungs. It can take 3 weeks or 3 months for symptoms to appear as the fungus spreads.

It can be treated with an antifungal medications. Untreated, it can lead to pneumonia and death as the fungus overwhelms the lungs.

It is not contagious.

The fungal spores that cause blastomycosis are common in the Upper Peninsula and in Wisconsin, especially in northern areas. Last fall, U.W. Health warned hunters to know the symptoms in case walking through the woods and moist soil kicked up mold spores.

In 2015, there was an outbreak of blastomycosis along the Wolf River. Forty-nine people were affected. One person died.

Public Health of Delta and Menominee Counties recommends the following precautions:

  • Wear personal protective equipment (facemasks or respirators, eye protection, and gloves) when engaging in higher-risk activities
  • Only move leaf litter when it is dry
  • Avoid moving or digging soil on windy days
  • Cover soil and yard materials
  • Ensure water has adequate drainage and doesn’t pool near work areas
  • Install walkways over wet areas to prevent walking through and disturbing muddy soil