title: No Observed Effect of Landscape Fragmentation on Pathogen Infection Prevalence in Blacklegged Ticks (Ixodes scapularis) in the Northeastern United States.
abstract: Pathogen prevalence within blacklegged ticks (Ixodes scapularis Say, 1821) tends to vary across sites and geographic regions, but the underlying causes of this variation are not well understood. Efforts to understand the ecology of Lyme disease have led to the proposition that sites with higher host diversity will result in lower disease risk due to an increase in the abundance of inefficient reservoir species relative to the abundance of species that are highly competent reservoirs. Although the Lyme disease transmission cycle is often cited as a model for this "dilution effect hypothesis", little empirical evidence exists to support that claim. Here we tested the dilution effect hypothesis for two pathogens transmitted by the blacklegged tick along an urban-to-rural gradient in the northeastern United States using landscape fragmentation as a proxy for host biodiversity. Percent impervious surface and habitat fragment size around each site were determined to assess the effect of landscape fragmentation on nymphal blacklegged tick infection with Borrelia burgdorferi and Anaplasma phagocytophilum. Our results do not support the dilution effect hypothesis for either pathogen and are in agreement with the few studies to date that have tested this idea using either a landscape proxy or direct measures of host biodiversity.
authors.affiliation: Department of Biological Sciences, Fordham University, Bronx, New York, United States of America; Vector Ecology Laboratory, Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York, United States of America.
authors.forename: Christine P
authors.initials: CP
authors.lastname: Zolnik
authors.affiliation: New York State Department of Health, Louis Calder Center, Armonk, New York, United States of America.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Falco
authors.affiliation: Department of Biological Sciences, Fordham University, Bronx, New York, United States of America.
authors.forename: Sergios-Orestis
authors.initials: SO
authors.lastname: Kolokotronis
authors.affiliation: Vector Ecology Laboratory, Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York, United States of America.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Daniels
mesh_terms: D041081:Anaplasma phagocytophilum / Q000235:genetics / Q000302:isolation & purification*; D000712:Anaplasmosis / Q000453:epidemiology / Q000635:transmission*; D063147:Animal Distribution; D000818:Animals; D000835:Animals, Wild / Q000469:parasitology; D001096:Arachnid Vectors / Q000382:microbiology*; D044822:Biodiversity; D025065:Borrelia burgdorferi / Q000235:genetics / Q000302:isolation & purification*; D003237:Connecticut / Q000453:epidemiology; D004269:DNA, Bacterial / Q000302:isolation & purification; D004197:Disease Reservoirs; D017753:Ecosystem; D019353:Endemic Diseases; D065928:Forests; D006702:Homing Behavior; D006801:Humans; D018884:Ixodes / Q000254:growth & development / Q000382:microbiology*; D008193:Lyme Disease / Q000453:epidemiology / Q000635:transmission*; D008954:Models, Biological; D009518:New York / Q000453:epidemiology; D060888:Real-Time Polymerase Chain Reaction; D012423:Rural Health; D013984:Tick Infestations / Q000453:epidemiology / Q000662:veterinary; D014504:Urban Health; D014507:Urbanization
chemical_list: D004269:DNA, Bacterial