Isolation of the Lyme Disease Spirochete Borrelia mayoniiFrom Naturally Infected Rodents in Minnesota

Borrelia mayoniiis a newly described member of the Borrelia burgdorferisensu lato complex that is vectored by the black-legged tick (Ixodes scapularisSay) and a cause of Lyme disease in Minnesota and Wisconsin. Vertebrate reservoir hosts involved in the enzootic maintenance of B. mayoniihave not yet been identified. Here, we describe the first isolation of B. mayoniifrom naturally infected white-footed mice (Peromyscus leucopusRafinesque) and an American red squirrel (Tamiasciurus hudsonicusErxleben) from Minnesota, thus implicating these species as potential reservoir hosts for this newly described spirochete.