Microbiome Composition and Borrelia Detection in Ixodes scapularis Ticks at the Northwestern Edge of Their Range

Abstract

Lyme disease-causing Borrelia burgdorferi has been reported in 10–19% of Ixodes ticks from Alberta, Canada, where the tick vector Ixodes scapularis is at the northwestern edge of its range. However, the presence of Borrelia has not been verified independently, and the bacterial microbiome of these ticks has not been described. We performed 16S rRNA bacterial surveys on female I. scapularis from Alberta that were previously qPCR-tested in a Lyme disease surveillance program. Both 16S and qPCR methods were concordant for the presence of Borrelia. The 16S studies also provided a profile of associated bacteria that showed the microbiome of I. scapularis in Alberta was similar to other areas of North America. Ticks that were qPCR-positive for Borrelia had significantly greater bacterial diversity than Borrelia-negative ticks, on the basis of generalized linear model testing. This study adds value to ongoing tick surveillance and is a foundation for deeper understanding of tick microbial ecology and disease transmission in a region where I. scapularis range expansion, induced by climate and land use changes, is likely to have increasing public health implications.

An exploratory study on the microbiome of northern and southern populations of Ixodes scapularis ticks predicts changes and unique bacterial interactions

“…Our results are not in complete coherence with other studies; [31][32][33][34] as those studies were conducted under a variety of different conditions to examine tick's microbiome. For example, Sperling et al, [34] analyzed the ticks collected off the cats and dogs from Alberta (Canada), whereas Kwan et al, [31] conducted their studies on Ixodes pacificus ticks. Several studies have also identified variation in microbiome among different tick species [35], sex [36][37], and geography [16,14].…”

“…A variation in the microbiota of Ixodes ticks with regard to geography and sex has been suggested [14]. Our results are not in complete coherence with other studies; [31][32][33][34] as those studies were conducted under a variety of different conditions to examine tick's microbiome. For example, Sperling et al, [34] analyzed the ticks collected off the cats and dogs from Alberta (Canada), whereas Kwan et al, [31] conducted their studies on Ixodes pacificus ticks.…”

An Exploratory Study on the Microbiome of Northern and Southern Populations of Ixodes scapularis Ticks Predicts Changes and Unique Bacterial Interactions

“…Our results are not in complete coherence with other studies [30][31][32][33][34], as those studies were conducted under a variety of different conditions to examine the tick's microbiome. For example, Sperling et al [34] analyzed the ticks collected off the cats and dogs from Alberta (Canada), whereas Kwan et al [31] conducted their studies on Ixodes pacificus ticks. Several studies have also identified variation in microbiome among different tick species [35], sexes [36,37], and geographies [14,16].…”

“…A variation in the microbiota of Ixodes ticks with regard to geography and sex has been suggested [14]. Our results are not in complete coherence with other studies [30][31][32][33][34], as those studies were conducted under a variety of different conditions to examine the tick's microbiome. For example, Sperling et al [34] analyzed the ticks collected off the cats and dogs from Alberta (Canada), whereas Kwan et al [31] conducted their studies on Ixodes pacificus ticks.…”

The bacterial biome of ticks and their wildlife hosts at the urban–wildland interface

“…The diagnostic value of 16S rRNA amplicon sequencing methods has not been thoroughly validated for tick-borne pathogens. One study, however, showed that ticks which tested positive for Borrelia using quantitative PCR methods also had a high abundance of Borrelia using amplicon bacterial metabarcoding [ 70 ]. Therefore, even though Ix.…”