Relapsing Fever Caused by Borrelia lonestari after Tick Bite in Alabama, USA

Emerg Infect Dis. 2023 Feb;29(2):441-444. doi: 10.3201/eid2902.221281.


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.

Publication types

  • Letter

MeSH terms

  • Alabama / epidemiology
  • Borrelia* / genetics
  • Humans
  • Phylogeny
  • Relapsing Fever* / diagnosis
  • Tick Bites* / complications

Supplementary concepts

  • Borrelia lonestari