Volume 29, Number 1—January 2023
Lyme disease is a multisystem disorder primarily caused by Borrelia burgdorferi sensu lato. However, B. garinii, which has been identified on islands off the coast of Newfoundland and Labrador, Canada, is a cause of Lyme disease in Eurasia. We report isolation and whole-genome nucleotide sequencing of a B. garinii isolate from a cotton mouse (Peromyscus gossypinus) in South Carolina, USA. We identified a second B. garinii isolate from the same repository. Phylogenetic analysis does not associate these isolates with the previously described isolates of B. garinii from Canada.
How and when B. garinii arrived in South Carolina remains unknown. There were no reported Lyme disease outbreaks in the southeastern United States in humans at the time the strains were deposited in the repository or during the subsequent 2 decades. This finding minimizes the urgency for an immediate new search for B. garinii in this region. Nonetheless, clinical vigilance for B. garinii in humans in this region seems warranted.
True to form, the CDC downplays the finding of a new strain which very well could explain why sick patients continue to be mis or undiagnosed due to faulty testing and strain diversity, which will never be picked up using current 2-tiered CDC testing because it doesn’t look for other strains.