Is composition of vertebrates an indicator of the prevalence of tick-borne pathogens?

Abstract

Communities of vertebrates tend to appear together under similar ranges of environmental features. This study explores whether an explicit combination of vertebrates and their contact rates with a tick vector might constitute an indicator of the prevalence of a pathogen in the quest for ticks at the western Palearctic scale. We asked how ‘indicator’ communities could be ‘markers’ of the actual infection rates of the tick in the field of two species of Borrelia (a bacterium transmitted by the tick Ixodes ricinus) . We approached an unsupervised classification of the territory to obtain clusters on the grounds of abundance of each vertebrate and contact rates with the tick. Statistical models based on Neural Networks, Random Forest, Gradient Boosting, and AdaBoost were detect the best correlation between communities’ composition and the prevalence of Borrelia afzelii and Borrelia gariniii in questing ticks. Both Gradient Boosting and AdaBoost produced the best results, predicting tick infection rates from the indicator communities. A ranking algorithm demonstrated that the prevalence of these bacteria in the tick is correlated with indicator communities of vertebrates on sites selected as a proof-of-concept. We acknowledge that our findings are supported by statistical outcomes, but they provide consistency for a framework that should be deeper explored at the large scale.

Perception of Ticks and Tick-Borne Diseases Worldwide

“…Future directions should include (e.g., [112,117,241,253,[255][256][257][258][259][260]) (a) systematic and comprehensive surveillance studies for ticks and TBD in both humans and animals, (b) development of innovative interventions for the control of tick infestations in domestic and wild hosts, (c) effective vaccines for controlling tick infestations in animal hosts and TBD in humans and animals, (d) implementation of regional and worldwide coordinated initiatives for more effective surveillance of ticks and TBD, detection of emerging species and diseases, and prevention of expansion worldwide, (e) application of a multidisciplinary One Health approach linking human, animal, and environmental health, (f) monitoring acaricide application and resistance in different regions, (g) transgenic and paratransgenic interventions in both hosts and ticks to control ticks and TBD, (h) modeling the effect of climate change and anthropogenic land use on the possible expansion of wild hosts and tick populations and incidence of TBD, (i) application of multiomic system biology approaches to the study of host immune-mediated mechanisms and identification of biomarkers in susceptible patients and animal hosts for efficacious disease diagnosis and treatment, and (j) communication to the general population and healthcare system of the risks associated with ticks and TBD and measures to reduce these risks. Acknowledgments: We acknowledge the discussion of these topics with colleagues worldwide and participating in multiple collaborations.…”

“…Most, if not all, species affecting livestock and pets in Europe may bite humans with a different pressure according to the climate gradient associated with the territory and with pathogen transmission. The pathogens carried by ticks are supported by populations of wild vertebrates, that have a different prominence according to the composition of the community of vertebrates [117]. According to the area of the territory, these associations of ticks-hosts (reservoirs) may change and therefore the array of transmitted pathogens may be different.…”