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

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. Graphical abstract

Presence of Anaplasma phagocytophilum Ecotype I in UK Ruminants and Associated Zoonotic Risk

“…Another recently published study, still on questing ticks, revealed a 4.7% prevalence of A. phagocytophilum in Wester Ross, the northwest area of the Scottish Highlands, with A. phagocytophilum being the most prevalent tick-borne pathogen detected. According to the authors, the majority of the strains (86%) were identified as the zoonotic ecotype I, probably maintained by red deer, and the remaining (14%) as the non-zoonotic ecotype II, probably maintained by roe deer [ 23 ]. An eco-epidemiological screening of the rodent community in West Wales revealed a low prevalence of A. phagocytophilum, which was detected only at one site in ticks collected from bank voles [ 24 ].…”

Assembly and Comparison of Ca. Neoehrlichia mikurensis Genomes

“…Ixodes ricinus also transmits Ca. Neoehrlichia mikurensis, which has been found all across Europe except for the United Kingdom [6][7][8]. The number of studies describing human infections involving Ca.…”

Protozoan co-infections and parasite influence on the efficacy of vaccines against bacterial and viral pathogens

“…Lyme disease causing spirochetal bacteria belonging to Borrelia burgdorferi sensu lato are also transmitted to different hosts by ticks (Stewart and Bloom, 2020). Increasing rate of co-infections by these two pathogens have been reported in the endemic regions of the United States (Swanson et al, 2006;Diuk-Wasser et al, 2016;Wormser et al, 2019) and Europe (Olsthoorn et al, 2021). Thus, in addition to B. burgdorferi-Babesia co-infections, simultaneous Babesia-Anaplasma phagocytophilum infections are also reported because tick vector and white footed mouse, Peromyscus leucopus (and other reservoir hosts) harbor several pathogens together.…”