Occurrence of tick-borne pathogens in questing Ixodes ricinus ticks from Wester Ross, Northwest Scotland

Olsthoorn, F., Sprong, H., Fonville, M., Rocchi, M., Medlock, J., Gilbert, L. and Ghazoul, J. (2021) Occurrence of tick-borne pathogens in questing Ixodes ricinus ticks from Wester Ross, Northwest Scotland. Parasites and Vectors, 14(1), 430. (doi: 10.1186/s13071-021-04946-5) (PMID:34446082) (PMCID:PMC8393815)

Abstract

Background: Lyme borreliosis and other tick-borne diseases emerge from increased interactions between humans, other animals, and infected ticks. The risk of acquiring a tick-borne infection varies across space and time, so knowledge of the occurrence and prevalence of pathogens in ticks can facilitate disease diagnosis in a specific area and the implementation of mitigation measures and awareness campaigns. Here we identify the occurrence and prevalence of several pathogens in Ixodes ricinus ticks in Wester Ross, Northwest Scotland, a region of high tourism and tick exposure, yet data-poor in terms of tick-borne pathogens. Methods: Questing I. ricinus nymphs (n = 2828) were collected from 26 sites in 2018 and 2019 and tested for the presence of tick-borne pathogens using PCR-based methods. Prevalence was compared with other regions of Scotland, England, Wales, and the Netherlands. Results: Anaplasma phagocytophilum (4.7% prevalence), Borrelia burgdorferi sensu lato (s.l.) (2.2%), Babesia from clade X (0.2%), Rickettsia helvetica (0.04%), and Spiroplasma ixodetis (0.4%) were detected, but no Neoehrlichia mikurensis, Borrelia miyamotoi, or Babesia microti. Typing of A. phagocytophilum using a fragment of the GroEL gene identified the presence of both ecotype I and ecotype II. Genospecies identification of Borrelia burgdorferi s.l. revealed B. afzelii (53% of infected nymphs), B. garinii (9%), B. burgdorferi sensu stricto (7%), and B. valaisiana (31%). We found similar prevalence of A. phagocytophilum in Wester Ross as in the Netherlands, but higher than in other parts of Great Britain. We found lower B. burgdorferi s.l. prevalence than in England or the Netherlands, and similar to some other Scottish studies. We found higher prevalence of B. valaisiana and lower prevalence of B. garinii than in other Scottish studies. We found S. ixodetis at much lower prevalence than in the Netherlands, and R. helvetica at much lower prevalence than in England and the Netherlands. Conclusions: As far as we know, this is the first description of S. ixodetis in Great Britain. The results are relevant for disease surveillance and management for public and veterinary health. The findings can also aid in designing targeted public health campaigns and in raising awareness among outdoor recreationists and professionals.

• Item Type: Articles
• Additional Information: F.O. is supported by the Chair of Ecosystem Management at ETH Zurich. H.S. and M.F. were supported by a grant the European Interreg North Sea Region program, as part of the NorthTick project. The pathogen detection was financially supported by the Dutch Ministry of Health, Welfare, and Sports. L.G. and M.R. were supported by the Scottish Government’s Rural and Environmental Science and Analytical Services Division (RESAS).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Rocchi, Dr Mara and Gilbert, Dr Lucy
• Authors: Olsthoorn, F., Sprong, H., Fonville, M., Rocchi, M., Medlock, J., Gilbert, L., and Ghazoul, J.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Parasites and Vectors
• Publisher: BioMed Central
• ISSN: 1756-3305
• ISSN (Online): 1756-3305
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Parasites and Vectors 14(1):430
• Publisher Policy: Reproduced under a Creative Commons License