We report an immunocompromised patient in Alabama, USA, 75 years of age, with relapsing fevers and pancytopenia who had spirochetemia after a tick bite. We identified Borrelia lonestari by using PCR, sequencing, and phylogenetic analysis. Increasing clinical availability of molecular diagnostics might identify B. lonestari as an emerging tickborne pathogen.
Keywords: Alabama; Borrelia lonestari; United States; bacteria; parasites; relapsing fever; tick; vector-borne infections; zoonoses.