Title: False detection ofCoxiella burnetii—what is the risk?
Abstract: The insertion sequence IS1111 is used for molecular detection of Coxiella burnetii but also found in Coxiella -like endosymbionts of ticks, presenting a risk of false positive detection of C. burnetii . Limited IS1111 sequences from Coxiella -like bacteria restrict in silico assessment of IS1111 assays. However, Coxiella -like bacteria detectable by IS1111 assays appear to be rare in tick populations, limiting the impact of false positives on C. burnetii prevalence estimations. C. burnetii can be distinguished from Coxiella -like bacteria using C. burnetii SNP genotyping assays. Such assays can be used for detection, but are best used as post hoc tests given the extreme sensitivity of assays that target the multiple copy IS1111.
Recently, Duron (2015) demonstrated the presence of IS1111 in Coxiella -like endosymbionts of ticks. This work adds to our knowledge of sequence diversity within IS1111 from Coxiella -like endosymbionts. Duron et al . (2015) also show that Coxiella -like endosymbionts are widespread among tick species. Detection assays for the Q fever pathogen, C. burnetii , often target portions of IS1111 (Kim et al . 2005; Klee et al . 2006; Loftis et al . 2006; Panning et al . 2008; de Bruin et al . 2011); the repetitive nature of IS1111 provides multiple targets for primer annealing, resulting in unparalleled detection sensitivity. Given the presence of IS1111 in Coxiella -like bacteria, Duron and colleagues (Duron 2015 …