Abstract
In Europe, Ixodes ricinus plays a major role as a vector of Borrelia burgdorferi sensu lato (s.l.) spirochaetes, the causative agents of Lyme borreliosis, among other pathogens. In unfed ticks, Borrelia spirochaetes experience prolonged nutrient restriction. However, only few studies exist with regard to Borrelia infections in unfed ticks of different physiological ages. Changing body dimensions of unfed ticks, due to the consumption of energy reserves, allow physiological age estimation. The present study investigated the relationship of morphometric age with Borrelia prevalence and spirochaete load in 1882 questing I. ricinus nymphs, collected at two different locations in northern Germany in 2020. In addition, Borrelia species composition was investigated by employing a reverse line blot (RLB) probe panel suitable for the detection of ten different B. burgdorferi s.l. species, as well as the relapsing-fever spirochaete B. miyamotoi. Overall, Borrelia prevalence was 25.8% (485/1882). Whilst there was no statistically significant difference in Borrelia prevalence between the different morphometric age groups, Borrelia infection intensity as determined by probe-based quantitative real-time PCR significantly declined with increasing morphometric age. Borrelia species differentiation by RLB was successful in 29.5% of positive ticks, and revealed B. afzelii as the dominating species (65.0% of the differentiated infections). Additionally, B. garinii, B. valaisiana, B. burgdorferi sensu stricto, B. spielmanii, and B. miyamotoi were detected.
Highlights
Ticks of the Ixodes ricinus species complex, I. ricinus in Europe, I. persulcatus in Asia, and I. scapularis in North America, are of major public health importance due to their vector function for various pathogens, including Borrelia burgdorferi sensu lato (s.l.)spirochaetes, the causative agents of Lyme borreliosis [1]
The present study investigated the relationship of morphometric age with Borrelia infection status and spirochaete load in 1882 questing I. ricinus nymphs, collected from
Apart from the abovementioned studies, little information is available regarding the development of Borrelia infections in unfed ticks over time, with regard to the different species of the B. burgdorferi s.l. complex present in Europe, which vary in their genetic content, reservoir association, replication dynamics during blood-feeding, pathogenic potential, and clinical manifestation [9]
Summary
Ticks of the Ixodes ricinus species complex, I. ricinus in Europe, I. persulcatus in Asia, and I. scapularis in North America, are of major public health importance due to their vector function for various pathogens, including Borrelia burgdorferi sensu lato (s.l.). In I. ricinus populations of Central Europe, the common seasonal pattern of tick activity includes a peak in spring and, in some years, a second, lower peak in autumn, while moulting occurs during the warmest months of the year [2] This pattern arises as ticks respond to ambient conditions, such as temperature and relative humidity. Apart from the abovementioned studies, little information is available regarding the development of Borrelia infections in unfed ticks over time, with regard to the different species of the B. burgdorferi s.l. complex present in Europe, which vary in their genetic content, reservoir association, replication dynamics during blood-feeding, pathogenic potential, and clinical manifestation [9]. B. miyamotoi [11,12]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
