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

Abstract

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.

Comparative vector competence of the Afrotropical soft tick Ornithodoros moubata and Palearctic species, O. erraticus and O. verrucosus, for African swine fever virus strains circulating in Eurasia

“…erraticus [25, 59] and O . verrucosus [33]. Sequencing and depositing or referencing voucher sequences of genetic markers commonly used in tick taxonomy should be a priority for vector competence studies [60], which will enhance our understanding of the role soft ticks can play as vectors of ASFV.…”

“…Pigs may become infected by ingesting biting flies like the stable fly, Stomoxys calcitrans , carrying ASFV [30]. Studies on the soft tick fauna in the Paleartic region identified species that could be ASFV vectors [31–33]. However, limited information exists on the vector competence of Palearctic soft tick species for ASFV strains currently circulating in Eurasia [34, 35].…”

Isolation and genetic characterization of a relapsing fever spirochete isolated from Ornithodoros puertoricensis collected in central Panama

“…Spirochetes passaged no more than five times in medium were grown in 50 ml culture tubes and genomic DNA was isolated by phenol-chloroform extraction, as previously described [ 10 ]. To evaluate plasmid content, pulsed-field electrophoresis was performed using a PPI-200 Programmable Power Inverter (MJ Research, Watertown, MA), as previously reported with minor modifications [ 11 ]. Genomic DNA (1 μg) from B .…”

“…We also amplified Borrelia DNA gyrase subunit B gene ( gyrB ), flagellin gene ( flaB ), rrs , and the intragenic spacer (IGS) locus by polymerase chain reaction (PCR). Table 1 lists the primer sequences used, and PCR was performed as previously described [ 11 ]. PCR amplicons were purified using QIAquick PCR Purification Kit (Qiagen, Hilden, Germany), and were Sanger sequenced by GeneWiz (South Plainfield, New Jersey, USA).…”

“…Spirochetes passaged no more than five times in medium were grown in 50 ml culture tubes and genomic DNA was isolated by phenol-chloroform extraction, as previously described [10]. To evaluate plasmid content, pulsed-field electrophoresis was performed using a PPI-200 Programmable Power Inverter (MJ Research, Watertown, MA), as previously reported with minor modifications [11]. Genomic DNA (1 μg) from B. turicatae 91E135, Borrelia parkeri SLO, Borrelia hermsii DAH, Borrelia anserina BA2, and the novel Borrelia were electrophoresed in 1% agarose gels with 0.5x TBE buffer (45 mM Tris, 45 mM boric acid, and 1.8 mM EDTA) for 15 min at 100 V and run on Program 3 for 40 hr at 90 V.…”