Abstract
BackgroundLandscape structure can affect pathogen prevalence and persistence with consequences for human and animal health. Few studies have examined how reservoir host species traits may interact with landscape structure to alter pathogen communities and dynamics. Using a landscape of islands and mainland sites we investigated how natural landscape fragmentation affects the prevalence and persistence of the zoonotic tick-borne pathogen complex Borrelia burgdorferi (sensu lato), which causes Lyme borreliosis. We hypothesized that the prevalence of B. burgdorferi (s.l.) would be lower on islands compared to the mainland and B. afzelii, a small mammal specialist genospecies, would be more affected by isolation than bird-associated B. garinii and B. valaisiana and the generalist B. burgdorferi (sensu stricto).MethodsQuesting (host-seeking) nymphal I. ricinus ticks (n = 6567) were collected from 12 island and 6 mainland sites in 2011, 2013 and 2015 and tested for B. burgdorferi (s.l.). Deer abundance was estimated using dung transects.ResultsThe prevalence of B. burgdorferi (s.l.) was significantly higher on the mainland (2.5%, 47/1891) compared to island sites (0.9%, 44/4673) (P < 0.01). While all four genospecies of B. burgdorferi (s.l.) were detected on the mainland, bird-associated species B. garinii and B. valaisiana and the generalist genospecies B. burgdorferi (s.s.) predominated on islands.ConclusionWe found that landscape structure influenced the prevalence of a zoonotic pathogen, with a lower prevalence detected among island sites compared to the mainland. This was mainly due to the significantly lower prevalence of small mammal-associated B. afzelii. Deer abundance was not related to pathogen prevalence, suggesting that the structure and dynamics of the reservoir host community underpins the observed prevalence patterns, with the higher mobility of bird hosts compared to small mammal hosts leading to a relative predominance of the bird-associated genospecies B. garinii and generalist genospecies B. burgdorferi (s.s.) on islands. In contrast, the lower prevalence of B. afzelii on islands may be due to small mammal populations there exhibiting lower densities, less immigration and stronger population fluctuations. This study suggests that landscape fragmentation can influence the prevalence of a zoonotic pathogen, dependent on the biology of the reservoir host.
Highlights
Landscape structure can affect pathogen prevalence and persistence with consequences for human and animal health
Of the 44 nymphs that tested positive for B. burgdorferi (s.l.), 63.6% (28/44) were infected with B. garinii, 22.7% (10/44) with B. burgdorferi (s.s.), 11.4% with B. valaisiana (5/44) and 2.3% with B. afzelii (1/ 44) (Fig. 2, Additional file 1: Table S3)
This study investigated whether landscape fragmentation affects the distribution and persistence of the tick-borne pathogen B. burgdorferi (s.l.) and three genospecies B. afzelii, B. garinii and B. burgdorferi (s.s.)
Summary
Landscape structure can affect pathogen prevalence and persistence with consequences for human and animal health. Using a landscape of islands and mainland sites we investigated how natural landscape fragmentation affects the prevalence and persistence of the zoonotic tick-borne pathogen complex Borrelia burgdorferi (sensu lato), which causes Lyme borreliosis. Landscape structure can influence the persistence of a pathogen by affecting the movement of hosts and vectors, and the potential for transmission. Pathogen persistence will depend on the degree of isolation of habitat patches, and a balance between colonization and extinction events [1, 2]. Colonization of a pathogen into new habitat patches is likely to be affected by the mobility and ecology of the host species. Host population dynamics, large seasonal or interannual fluctuations, can contribute to stochastic fadeout of a pathogen within patches [3]
Sign-in/Register to view highlights & summary 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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
