title: Spatial distribution of seroprevalence for Anaplasma phagocytophilum, Borrelia burgdorferi, Ehrlichia canis, and Dirofilaria immitis in dogs in Washington, Oregon, and California.
abstract: BACKGROUND
  In the US little spatially defined information regarding exposure to most vector-borne pathogens in dogs is available for the states of California (CA), Oregon (OR), and Washington (WA).
  
  
  OBJECTIVE
  The purpose of the present study was to evaluate the spatial distribution of seroprevalence for 4 vector-borne pathogens, Anaplasma phagocytophilum, Borrelia burgdorferi, Ehrlichia canis, and Dirofilaria immitis, across the 3 western coastal states of the contiguous United States that extend from the northern Mexican to the southern Canadian border.
  
  
  METHODS
  A convenience sample, targeting blood from 20 pet dogs per county across CA, OR, and WA, was evaluated using a canine point-of-care ELISA kit. Geographic coordinates of home zip code were displayed using a geographic information system. A total of 2431 dogs from CA, OR, and WA were tested.
  
  
  RESULTS
  The overall seroprevalence was highest for A. phagocytophilum (2.4%), followed by B. burgdorferi (1.2%), and E. canis (0.7%). The prevalence of infection with D. immitis was 0.7%. At the individual dog level, there was a significant association between seropositivity to B. burgdorferi and A. phagocytophilum (odds ratio=18.7, 95% confidence interval=6.8-47.1). For most positive results, prevalence tended to decrease with increasing latitude; thus, the highest rates of seropositivity occurred in CA, followed by OR, and then WA; one exception was seropositivity for B. burgdorferi, which was higher in WA (0.38%) than in OR (0.15%), but considerably lower than in CA (2.00%). In WA, dogs that tested positive for A. phagocytophilum, E. canis, and B. burgdorferi were in the southern Puget Sound area. For D. immitis, none of the dogs in WA was positive.
  
  
  CONCLUSIONS
  Seropositivity for vector-borne pathogens is broadly but patchily distributed in dogs in CA, OR, and WA.
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Carrade
authors.forename: Janet
authors.initials: J
authors.lastname: Foley
authors.forename: Michael
authors.initials: M
authors.lastname: Sullivan
authors.forename: Colin W
authors.initials: CW
authors.lastname: Foley
authors.forename: Jane E
authors.initials: JE
authors.lastname: Sykes
mesh_terms: D041081:Anaplasma phagocytophilum / Q000276:immunology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000909:Antibodies, Helminth / Q000097:blood; D025065:Borrelia burgdorferi / Q000276:immunology; D002140:California / Q000453:epidemiology; D016001:Confidence Intervals; D003710:Demography / Q000706:statistics & numerical data; D004183:Dirofilaria immitis / Q000276:immunology; D004184:Dirofilariasis / Q000453:epidemiology*; D004283:Dog Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000469:parasitology; D004285:Dogs; D041061:Ehrlichia canis / Q000276:immunology*; D016873:Ehrlichiosis / Q000453:epidemiology / Q000662:veterinary*; D005260:Female; D008193:Lyme Disease / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D009922:Oregon / Q000453:epidemiology; D016036:Seroepidemiologic Studies; D014861:Washington / Q000453:epidemiology
chemical_list: D000907:Antibodies, Bacterial; D000909:Antibodies, Helminth