Evidence of Infections by Anaplasma phagocytophilum and Borrelia burgdorferi sl in American Black Bears, Woodrats, and Domestic Dogs From Inland Forest Habitats of Northern California
American Association of Zoo Veterinarians Conference 2004
Richard N. Brown1, PhD, DVM; Monet Belltawn1; Mourad W. Gabriel1; Jamie L. Sajecki1,2; J. Mark Higley2, MS; Janet E. Foley3, DVM, PhD
1Department of Wildlife, Humboldt State University, Arcata, CA, USA; 2Hoopa Tribal Forestry, Hoopa, CA, USA; 3Center for Vector-Borne Disease Research, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
Abstract
Transmission cycles of Anaplasma phagocytophilum and Borrelia burgdorferi sl appear parallel with reservoirs in wild rodents and transmission by Ixodes spp. ticks. Dusky-footed woodrats are the putative reservoir hosts of both of these organisms in California. We report high seropositivity to both organisms in woodrats, American black bears, and domestic dogs sampled in inland forest habitats, and DNA of A. phagocytophilum was PCR-amplified from 10% of woodrats and 3.8% of bears, but none of the dogs, suggesting greater risk to humans than is appreciated locally. However, the sequence of DNA typed as A. phagocytophilum from woodrats appears slightly different from reported sequences. Moreover, current evidence suggests that dusky-footed woodrats are the reservoir for Borrelia bissettii (a genospecies closely related to B. burgdorferi within the B. burgdorferi sl complex) but they may not be the most important reservoir of B. burgdorferi ss, the primary pathogen associated with human Lyme disease in the western US. Thus, the reservoir(s) of both of these important zoonotic pathogens remains unclear, at least in northern California.