CNN — Ninety-three confirmed or probable cases of blastomycosis have been identified in Michigan's Delta and Menominee counties, according to the local health department, and they are believed to be associated with a paper mill in the town of Escanaba.
Blastomycosis is caused by a fungus, Blastomyces, that lives in the environment, especially in moist soil and decomposing matter like wood or leaves, according to the US Centers for Disease Control and Prevention. It is predominantly found in the Midwest and the South, particularly around the Ohio and Mississippi rivers and the Great Lakes.
There are only one or two cases per 100,000 people each year in states where blastomycosis is a reportable condition, according to the CDC. One analysis found 1,216 deaths related to the illness from 1990 to 2010.
People can breathe in these microscopic fungal spores, and although most of them won't get sick, some will develop symptoms like a fever or cough between three weeks and three months later, the CDC says. Other symptoms may include chest pain, trouble breathing, night sweats, fatigue, weight loss, and muscle or joint pain, according to Public Health Delta & Menominee Counties. In rare cases, the infection can spread outside the lungs to places like the skin, bones, brain and spinal cord.
Blastomycosis does not spread from person to person. It's treated with antifungal medication that must be taken for a period ranging from six months to a year, depending on the severity of the illness and the person's overall health.
Nineteen of the cases linked with Escanaba Billerud Paper Mill have been confirmed by culture or microscope, and the other 74 are probable, meaning the person has symptoms of blastomycosis and a positive antigen or antibody test, the health department says.
"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," Billerud Escanaba Mill Operations Vice President Brian Peterson said in a statement from the health department.
