The dusky-footed woodrat (neotoma fuscipes) is susceptible to infection by anaplasma phagocytophilum originating from woodrats, horses, and dogs

Nathan C. Nieto, John E Madigan, Janet E Foley

Research output: Contribution to journalArticle

12 Scopus citations


The dusky-footed woodrat (Neotomafuscipes) is the putative reservoir for Anaplasma phagocytophilum in the western United States based on high prevalence of A. phagocytophilum genetic material detected by polymerase chain reaction (PCR), high antibody prevalence, and infestation with the vector tick Ixodes pacifiais. Following inoculation of nine wild-caught woodrats with woodrat-, canine-, or equine-origin A. phagocytophilum, all became PCR-positive and seroconverted. However, when PCR-positive woodrat blood was delivered as inoculum to three horses, the horses never became clinically ill, PCR-positive, or antibody-positive. Each horse was subsequently infected with either the equine- or chipmunk-origin A. phagocytophilum, resulting in clinical anaplasmosis. Our data show that woodrats are permissive to several strains of A. phagocytophilum, but strains originating from woodrats did not cause clinical disease in horses.

Original languageEnglish (US)
Pages (from-to)810-817
Number of pages8
JournalJournal of Wildlife Diseases
Issue number3
StatePublished - Jul 2010



  • Dusky-footed woodrat
  • Granulocytic anaplasmosis
  • Host-tropism
  • Ixodes pacifiais
  • Neotoma fuscipes
  • Sylvatic reservoir
  • Tick-borne disease

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology

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