Identification of novel Coxiella burnetii genotypes from Ethiopian ticks

摘要

Background:udCoxiella burnetiiud, the etiologic agent of Q fever, is a highly infectiousudzoonotic bacterium. Genetic information about the strains of this worldwideuddistributed agent circulating on the African continent is limited. The aim of theudpresent study was the genetic characterization ofudC. burnetiiudDNA samplesuddetected in ticks collected from Ethiopian cattle and their comparison with otherudgenotypes found previously in other parts of the world.udMethodology/Principal Findings:udA total of 296 tick samples were screened byudreal-time PCR targeting the ISud1111udregion ofudC. burnetiiudgenome and from the 32udpositive samples, 8 cases with sufficientudC. burnetiiudDNA load (udAmblyommaudcohaerensud,nud5ud6;udA. variegatumud,nud5ud2) were characterized by multispacer sequenceudtyping (MST) and multiple-locus variable-number tandem repeat analysis (MLVA).udOne novel sequence type (ST), the proposed ST52, was identified by MST. TheudMLVA-6 discriminated the proposed ST52 into two newly identified MLVAudgenotypes: type 24 or AH was detected in bothudAmblyommaudspecies while type 26udor AI was found only inudA. cohaerensud.udConclusions/Significance:udBoth the MST and MLVA genotypes of the presentudwork are closely related to previously described genotypes found primarily in cattleudsamples from different parts of the globe. This finding is congruent with the sourceudhosts of the analyzed Ethiopian ticks, as these were also collected from cattle. Theudpresent study provides genotype information ofudC. burnetiiudfrom this seldom studiedudEast-African region as well as further evidence for the presumed host-specificudadaptation of this agent.