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Home / Equine Research Bank / J Med Entomol / Ixodes pacificus (Acari: Ixodidae) as a vector of Ehrlichia ...
Journal of medical entomology1996; 33(1); 1-5; doi: 10.1093/jmedent/33.1.1

Ixodes pacificus (Acari: Ixodidae) as a vector of Ehrlichia equi (Rickettsiales: Ehrlichieae).

Abstract: Ehrlichia equi, a rickettsia described from horses in California 30 yr ago, causes equine granulocytic ehrlichiosis throughout the Americas and possibly Europe. Here, we report experimental transmission of E. equi from infected to susceptible horses through bites of western blacklegged ticks, Ixodes pacificus (Cooley & Kohls). In preliminary field studies, only I. pacificus consistently infested horses and vegetation at 3 locations with contemporary cases of equine ehrlichosis, and in particular, I. pacificus was the only species found attached to all of the infected horses. Exposure to bites of ticks in the genus Ixodes poses previously unrecognized and serious health risks to humans and animals.
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Publication Date: 1996-01-01 PubMed ID: 8906897DOI: 10.1093/jmedent/33.1.1Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • P.H.S.

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research shows that Ehrlichia equi, a disease-causing bacterium in horses, can be transmitted from infected horses to non-infected ones by the western blacklegged tick, Ixodes pacificus.

Overview of Study

  • The principal subject of the research article is the bacterium Ehrlichia equi, which is a cause of equine granulocytic ehrlichiosis, a disease that affects horses and has been detected across the Americas and possibly in Europe too.
  • This rickettsia was first described in California approximately three decades prior to this research.
  • The researcher’s primary aim was to investigate whether this pathogen could be transmitted from infected horses to vulnerable ones through the bite of a specific tick species, the western blacklegged tick or Ixodes pacificus (Cooley & Kohls).

Methodology and Findings

  • The researchers took on preliminary field studies to examine the presence and role of ticks in locations with reported cases of equine ehrlichiosis.
  • In these locations, they found that it was specifically the Ixodes pacificus tick that consistently infested horses and the local vegetation, indicating that this type of tick might be a potential vector for the disease.
  • Importantly, the researchers found that the Ixodes pacificus tick was the only species that was found attached to all infected horses in the study. This observation further supports the suggestion that this specific tick is the likely vector for the disease.
  • The researchers concluded that exposure to bites from ticks in the genus Ixodes, which includes the western blacklegged tick, presents significant and previously unrecognised health risks to both humans and animals.

Implications of the Study

  • The study’s findings could contribute significant value to the field of veterinary health, particularly to equine health.
  • If these findings are widely accepted, they could lead to the implementation of preventative measures to minimise exposure to these ticks, like producing repellent products or creating vaccines against the bacteria.

Cite This Article

APA
Richter PJ, Kimsey RB, Madigan JE, Barlough JE, Dumler JS, Brooks DL. (1996). Ixodes pacificus (Acari: Ixodidae) as a vector of Ehrlichia equi (Rickettsiales: Ehrlichieae). J Med Entomol, 33(1), 1-5. https://doi.org/10.1093/jmedent/33.1.1

Publication

Journal of medical entomology
ISSN: 0022-2585
NlmUniqueID: 0375400
Country: England
Language: English
Volume: 33
Issue: 1
Pages: 1-5

Researcher Affiliations

Richter, P J
  • Division of Comparative Medicine, University of California-San Diego, La Jolla 92093, USA.
Kimsey, R B
    Madigan, J E
      Barlough, J E
        Dumler, J S
          Brooks, D L

            MeSH Terms

            • Animals
            • Antibodies, Bacterial / blood
            • Arthropod Vectors / microbiology
            • Base Sequence
            • DNA, Bacterial / genetics
            • Ehrlichia / genetics
            • Ehrlichia / immunology
            • Ehrlichia / isolation & purification
            • Ehrlichiosis / immunology
            • Ehrlichiosis / microbiology
            • Ehrlichiosis / transmission
            • Female
            • Horses
            • Ixodes / microbiology
            • Male
            • Molecular Sequence Data

            Grant Funding

            • RR07038 / NCRR NIH HHS

            Citations

            This article has been cited 45 times.
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