Candidatus Coxiella massiliensis Infection

Abstract

Bacteria genetically related to Coxiella burnetii have been found in ticks. Using molecular techniques, we detected Coxiella-like bacteria, here named Candidatus Coxiella massiliensis, in skin biopsy samples and ticks removed from patients with an eschar. This organism may be a common agent of scalp eschar and neck lymphadenopathy after tick bite.

Keywords: Candidatus Coxiella massiliensis; Coxiella-like bacteria; SENLAT; bacteria; eschar; parasites; scalp eschar and neck lymphadenopathy after tick bite; skin biopsy; ticks; vector-borne infections; vectorborne.

Figure 1

Phylogenetic tree based on GroEL sequences including Coxiella-like strains of bacteria from ticks, Coxiella burnetii reference strains, and bacterial outgroups. GroEL gene sequences (Technical Appendix Table 2) were aligned by using ClustalW (http://www.ebi.ac.uk/Tools/msa/), and phylogenetic inferences were obtained by using Bayesian phylogenetic analysis with TOPALi 2.5 software (http://www.topali.org/) and the integrated MrBayes (http://mrbayes.sourceforge.net/) application with the HKY+Г (Hasegawa-Kishino-Yano plus gamma) substitution model for the first and third codons and the JC model for the second codon. GenBank accession numbers are indicated first, followed by the tick host. Numbers at nodes are bootstrap values obtained by repeating the analysis 100 times to generate a majority consensus tree. The final dataset contained 576 positions. Scale bar indicates 10% nucleotide sequence divergence.

Figure 2

Immunofluorescence assay results of samples from 3 Candidatus Coxiella massiliensis–infected patients and 1 noninfected person (negative control). Original magnification ×63.