ESCANABA — Local health officials are investigating a cluster of pneumonia cases among Escanaba paper mill workers that may be caused by a fungus.

On Feb. 28, Public Health Delta & Menominee Counties was notified of several atypical pneumonia infections in individuals employed at the Escanaba Billerud Paper Mill. To date there have been 15 cases identified that are being investigated. Symptoms for these patients began in January and February.

Early testing has indicated the infections may be caused by a fungal infection called blastomycosis. Additional testing to confirm these results may take a couple of weeks and is underway.

The Daily Press has independently confirmed two cases of blastomycosis among workers at the Escanaba mill, one of which was diagnosed after testing at St. Mary’s Hospital in Green Bay, Wis., and the other of which was diagnosed at UP Health Systems Marquette.

Blastomycosis is a fungal disease associated with a fungus that grows in moist soil and decomposing matter, such as wood and leaves. These infections are exceedingly rare, but the U.P. is a known risk area for blastomycosis infection.

On average, only 26 cases have been reported annually for the entire state of Michigan over the past five years.

People can get blastomycosis infection by breathing in fungal spores from the air. It does not spread from person to person or between animals and people. People who spend their time near moist soil, such as near lakes and rivers; who participate in activities like forestry work, hunting, and camping in wooded areas; and individuals exposed to disturbed soils may be at a higher risk of getting blastomycosis.

Most people who breathe in blastomycosis spores do not get sick. Those who do get sick can develop symptoms such as fever, chest pain, difficulty breathing, night sweats, fatigue, weight loss, muscle aches, joint pain and cough, sometimes with blood. Symptoms usually appear between three weeks and three months after exposure.

Blastomycosis can be treated with anti-fungal medications prescribed by a medical provider. Treatment is especially effective when administration begins as soon after symptoms as possible.

Because the fungus that causes blastomycosis occurs in the environment, it is not possible to completely avoid being exposed. People with weakened immune systems may want to consider avoiding activities that involve disrupting soil in areas where blastomycosis is found.

There is no vaccine to prevent blastomycosis.

PHDM offers the following tips to reduce a person’s risk of exposure to blastomycosis:

— Wear personal protective equipment — such as face masks or respirators, eye protection, and gloves — when engaging in higher risk activities

— Only move leaf litter when it is dry

— Avoid moving or digging in 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

Health officials from PHDM and the Michigan Department of Health and Human Services, along with Billerud Paper Mill occupational health staff, are working together to investigate the cluster of illnesses.

Because the fungus responsible for blastomycosis is common in the environment in the U.P., identifying a specific source or point of exposure can be difficult. Health officials are actively working to identify any exposures common among the ill individuals.

Information and guidance have also been distributed to local medical providers to assist in the recognition and appropriate diagnosis of blastomycosis.