The spread of toxic fungal spores in a Wisconsin neighborhood—probably spread by recent construction in the area—caused a rare infection outbreak that killed one person. State health officials reported the number of illnesses and deaths in their weekly report on Friday.
In all, the outbreak cluster included five pets and four people, with the onset of symptoms spanning from October 2021 to February 2022. Although two of the cases in humans were mild, the other two required hospitalization with severe cases. Five dogs were reported to have mild to moderate cases.
The outbreak was caused by a poorly understood fungus Blastomyces (b. dermatitis And b. Gilchristie), which hides in moist soil and decaying organic matter, such as wood and leaves, often near water. The Centers for Disease Control and Prevention speculates that fungi may cause Exists throughout eastern America, but its distribution is uneven. It is often found in the Ohio and Mississippi River valleys and around the Great Lakes. Parts of Wisconsin and Minnesota are considered hotspots.
Blastomyces Its presence is often known when it is disturbed or scooped out—often by literal digging—causing the spores to become airborne. If the spores are inhaled by humans or animals, they can cause an infection called blastomycosis, a non-contagious infection that can occur three weeks to three months after exposure. About half of people infected will have no symptoms or ill effects, but the other half may develop symptoms of a respiratory infection, such as cough, fever and shortness of breath. For many, the symptoms will clear up on their own, but for some—especially the immunocompromised, those who smoke, and those with lung disease—the infection can spread throughout the body and become life-threatening if not treated aggressively with antifungal medications. . Depending on the severity, treatment courses can range from six months to a year.
In general, blastomycosis is rare in the United States. In states where the infection is reportable, the incidence is about one or two cases per 100,000 people per year. But, in some hotspots in Wisconsin, the incidence can be as high as 40 to 50 per 100,000 per year. Surprisingly, though, the region where the newly reported outbreak occurred is not considered one of those hot spots.
An outbreak has occurred In northwestern St. Croix County, in the unincorporated community of Boardman, a small area adjacent to Willow River, which flows into the St. Croix River. The entire area is near the Minnesota border, across from Minneapolis.
Find the fungus
Typically, St. Croix reports one to five blastomycosis cases per year. However, this particular area of the county has not seen a human blastomycosis case in at least 10 years, although there was an unofficial report of a dog dying of the infection in 2021.
In February 2022, an “astute” veterinarian alerted health officials after four dogs were diagnosed with blastomycosis in recent weeks, all living within a one-mile radius near the Willow River in Boardman, MWWR reported. Once alerted, local health officials looked at surveillance data and identified two human cases in the same small area. Officials responded by sending letters to residents of potential clusters of cases. Two more people were diagnosed with the infection after the notification.
It is not clear what exactly caused the fire Blastomyces This is in a residential area, but an environmental assessment pointed to unpaved walking paths along the river – as well as recent development in the area. “Constructions in this neighborhood may have sprung up in the last decade Blastomyces spores,” the authors noted.
For those who live in affected areas, there is little they can do despite being aware of the ever-present fungus risk around their property. There are no commercially available tests for detection Blastomyces In the environment and even if there were, environmental tests are basically useless. As the CDC notes: “When a soil sample tests positive blastomyces, It’s not necessarily the source of infection, and when a sample is negative, that doesn’t mean the fungus isn’t in the soil.”
in St. Croix, Officials advise residents Basically, tread lightly: “You can reduce your risk of exposure by limiting activities that can disturb soil and plant matter,” notes Country. “High risk” activities include “gardening, camping, hunting, hiking, driving all-terrain vehicles, clearing brush, or digging and construction projects.” For pets, the county advises “avoid activities such as sniffing or digging at water’s edge, landscaped areas or wooded terrain.”