Isolation and Molecular Characterization of Tick-Borne Relapsing Fever Borrelia Infecting Ornithodoros (Pavlovskyella) verrucosus Ticks Collected in Ukraine

Serhii Filatov, Aparna Krishnavajhala, Brittany A. Armstrong, Alexander R. Kneubehl, Nathan C. Nieto, Adalberto A.Pérez De León, Job E. Lopez

Research output: Contribution to journalArticle


Background: Tick-borne relapsing fever (TBRF) is a neglected zoonotic bacterial disease known to occur on 5 continents. We report a laboratory-acquired case of TBRF caused by Borrelia caucasica, which is endemic in Ukraine and transmitted by Ornithodoros verrucosus ticks. Methods: We isolated spirochetes and characterized them by partially sequencing the 16s ribosomal ribonucleic acid (rrs), flagellin (flaB), and deoxyribonucleic acid gyrase (gyrB) genes and conducting a phylogenetic analysis. Results: These analyses revealed a close relationship of Ukrainian spirochetes with the Asian TBRF species, Borrelia persica. The taxonomic and nomenclature problems related to insufficient knowledge on the spirochetes and their vectors in the region are discussed. Conclusions: Although these findings enhance our understanding of species identities for TBRF Borrelia in Eurasia, further work is required to address the neglected status of TBRF in this part of the world. Public health practitioners should consider TBRF and include the disease into differential diagnosis of febrile illnesses with unknown etiology.

Original languageEnglish (US)
Pages (from-to)804-811
Number of pages8
JournalJournal of Infectious Diseases
Issue number5
StatePublished - Feb 18 2020



  • argasid
  • Borrelia
  • tick-borne relapsing fever
  • Ukraine

ASJC Scopus subject areas

  • Immunology and Allergy
  • Infectious Diseases

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