High Prevalence and Low Diversity of Rickettsia in Dermacentor reticulatus Ticks, Central Europe

Abstract

We collected 1,671 Dermacentor reticulatus ticks from 17 locations in the Czech Republic, Slovakia, and Hungary. We found 47.9% overall prevalence of Rickettsia species in ticks over all locations. Sequence analysis confirmed that all tested samples belonged to R. raoultii, the causative agent of tick-borne lymphadenopathy.

Keywords: Czech Republic; DEBONEL; Dermacentor reticulatus ticks; Dermacentor spp.-borne necrosis erythema lymphadenopathy; Hungary; Rickettsia; Rickettsia raoultii; Slovakia; TIBOLA; tick-borne infections; tick-borne lymphadenopathy.

Figure

Phylogenetic tree inferred from outer membrane protein ompB region (600 bp) showing 4 separate branches of Rickettsia spp. in ticks. The sequences we obtained (bold) were placed into highly supported subclade corresponding with R. raoultii. First sequence (haplotype 1) shows 100% identity with GenBank accession no. DQ365797 from D. reticulatus ticks from France. Second sequence (haplotype 2) has 100% identity with GenBank accession no. HQ232262 from D. reticulatus ticks from Germany. The numbers at the nodes show posterior probabilities under the Bayesian inference/bootstrap values for maximum likelihood. GenBank accession number are provided for reference sequences. Branch lengths indicate expected numbers of substitutions per nucleotide site.