title: An Invasive Mammal (the Gray Squirrel, Sciurus carolinensis) Commonly Hosts Diverse and Atypical Genotypes of the Zoonotic Pathogen Borrelia burgdorferi Sensu Lato.
abstract: Invasive vertebrate species can act as hosts for endemic pathogens and may alter pathogen community composition and dynamics. For the zoonotic pathogen Borrelia burgdorferi sensu lato, the agent of Lyme borreliosis, recent work shows invasive rodent species can be of high epidemiological importance and may support host-specific strains. This study examined the role of gray squirrels (Sciurus carolinensis) (n = 679), an invasive species in the United Kingdom, as B. burgdorferi sensu lato hosts. We found that gray squirrels were frequently infested with Ixodes ricinus, the main vector of B. burgdorferi sensu lato in the United Kingdom, and 11.9% were infected with B. burgdorferi sensu lato. All four genospecies that occur in the United Kingdom were detected in gray squirrels, and unexpectedly, the bird-associated genospecies Borrelia garinii was most common. The second most frequent infection was with Borrelia afzelii. Genotyping of B. garinii and B. afzelii produced no evidence for strains associated with gray squirrels. Generalized linear mixed models (GLMM) identified tick infestation and date of capture as significant factors associated with B. burgdorferi sensu lato infection in gray squirrels, with infection elevated in early summer in squirrels infested with ticks. Invasive gray squirrels appear to become infected with locally circulating strains of B. burgdorferi sensu lato, and further studies are required to determine their role in community disease dynamics. Our findings highlight the fact that the role of introduced host species in B. burgdorferi sensu lato epidemiology can be highly variable and thus difficult to predict.
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland Caroline.Millins@glasgow.ac.uk.
authors.forename: Caroline
authors.initials: C
authors.lastname: Millins
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Magierecka
authors.affiliation: James Hutton Institute, Craigiebuckler, Aberdeen, Scotland.
authors.forename: Lucy
authors.initials: L
authors.lastname: Gilbert
authors.affiliation: School of Veterinary Medicine, University of Glasgow, Glasgow, Scotland.
authors.forename: Alissa
authors.initials: A
authors.lastname: Edoff
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland.
authors.forename: Amelia
authors.initials: A
authors.lastname: Brereton
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kilbride
authors.affiliation: The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Matt
authors.initials: M
authors.lastname: Denwood
authors.affiliation: School of Environment and Life Sciences, University of Salford, Salford, England.
authors.forename: Richard
authors.initials: R
authors.lastname: Birtles
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland.
authors.forename: Roman
authors.initials: R
authors.lastname: Biek
mesh_terms: D000818:Animals; D015748:Borrelia burgdorferi Group / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004199:Disease Vectors; D004478:Ectoparasitic Infestations / Q000469:parasitology; D014644:Genetic Variation; D005838:Genotype; D018884:Ixodes / Q000382:microbiology*; D008193:Lyme Disease / Q000382:microbiology / Q000662:veterinary*; D008969:Molecular Sequence Data; D012589:Sciuridae / Q000382:microbiology* / Q000469:parasitology; D012621:Seasons; D017422:Sequence Analysis, DNA; D006113:United Kingdom
chemical_list: D004269:DNA, Bacterial