New Lyme Disease-Causing Bacteria Species Identified in Upper Midwest

Why it matters locally: The discovery of *Borrelia mayonii* as a cause of Lyme disease in the Upper Midwest was a collaborative effort involving Wisconsin's health department. Identification of the new species will influence diagnosis and treatment of Lyme disease in the state.

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Atlanta, GA - A new bacterial species responsible for causing Lyme disease in humans has been identified in the Upper Midwest, according to a report released by the Centers for Disease Control and Prevention (CDC). The bacteria, named *Borrelia mayonii*, is a newly discovered cause of Lyme disease in North America. Previously, *Borrelia burgdorferi* was believed to be the only bacteria responsible for Lyme disease cases in North America. The discovery was a collaborative effort among the CDC, Mayo Clinic, and health departments in Minnesota, Wisconsin, and North Dakota. The new species was identified through laboratory testing of patient samples. While *Borrelia mayonii* causes Lyme disease, some symptoms differ from those associated with *Borrelia burgdorferi* infection. According to the CDC, patients infected with *Borrelia mayonii* may experience nausea, diffuse rashes, and higher concentrations of bacteria in their blood. Public health officials are continuing to monitor the prevalence and geographic distribution of *Borrelia mayonii*. The CDC states that efforts are underway to better understand the characteristics of the new bacteria and its impact on Lyme disease diagnosis and treatment. The diagnosis of Lyme disease caused by *Borrelia mayonii* is performed through standard laboratory tests.