Attempted transmission of Ehrlichia risticii, causative agent of Potomac horse fever, by the ticks, Dermacentor variabilis, Rhipicephalus sanguineus, Ixodes scapularis and Amblyomma americanum.
Abstract: Dermacentor variabilis, Rhipicephalus sanguineus, Amblyomma americanum, and Ixodes scapularis ticks were investigated for their ability to transmit Potomac horse fever. Larval and nymphal ticks were exposed to Ehrlichia risticii by feeding on mice inoculated with the organism. Molted exposed ticks were then allowed to feed on susceptible ponies or mice. No evidence of transmission, either clinically or by detection of antibodies to E. risticii in mice or ponies, was observed for any tick species examined.
Publication Date: 1990-01-01 PubMed ID: 2307070DOI: 10.1007/BF01193380Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
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 study investigates the ability of certain tick species to transmit Potomac horse fever. The researchers found no evidence that these ticks could transmit the disease.
Introduction
Potomac horse fever is a disease that primarily affects horses and is caused by a bacterium called Ehrlichia risticii. This research paper aims at studying whether four types of ticks, Dermacentor variabilis, Rhipicephalus sanguineus, Amblyomma americanum, and Ixodes scapularis, can transmit this bacterium and thus, Potomac horse fever.
Methodology
- The larval and nymphal stages of the four kinds of ticks were exposed to Ehrlichia risticii. This was done by allowing the ticks to feed on mice that had been inoculated with the bacteria.
- Ticks that survived and molted were then allowed to feed on ponies or mice that were susceptible to the bacteria.
- The researchers then carefully monitored the mice and ponies for signs of Potomac horse fever, and tested their blood for the presence of antibodies to Ehrlichia risticii.
Results
- No evidence of transmission was found in any of the four tick species examined.
- This was determined by the lack of clinical symptoms of the disease, and the absence of antibodies to Ehrlichia risticii in the blood of the ponies and mice the ticks had fed on after exposure.
Conclusion
This study provides valuable insights into the vectorial capacity of certain tick species for transmitting Potomac horse fever. No evidence was found that the tick species Dermacentor variabilis, Rhipicephalus sanguineus, Amblyomma americanum or Ixodes scapularis can transmit this disease, highlighting the need to investigate other potential vectors.
This information could help in the development of new strategies for controlling the spread of Potomac horse fever, by focusing on the true vectors of the disease.
Cite This Article
APA
Hahn NE, Fletcher M, Rice RM, Kocan KM, Hansen JW, Hair JA, Barker RW, Perry BD.
(1990).
Attempted transmission of Ehrlichia risticii, causative agent of Potomac horse fever, by the ticks, Dermacentor variabilis, Rhipicephalus sanguineus, Ixodes scapularis and Amblyomma americanum.
Exp Appl Acarol, 8(1-2), 41-50.
https://doi.org/10.1007/BF01193380 Publication
Researcher Affiliations
- Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg 24061.
MeSH Terms
- Animals
- Arachnid Vectors / microbiology
- Dermacentor / microbiology
- Ehrlichia / isolation & purification
- Horse Diseases / transmission
- Horses
- Larva / microbiology
- Mice
- Nymph / microbiology
- Rickettsiaceae / isolation & purification
- Rickettsiaceae Infections / transmission
- Rickettsiaceae Infections / veterinary
- Ticks / microbiology
References
This article includes 15 references
- Carroll JF, Schmidtmann ET. American dog tick (Acari: Ixodidae), summer activity on equine premises enzootic for Potomac horse fever in south-central Maryland.. J Econ Entomol 1986 Feb;79(1):62-6.
- Kocan KM, Venable JH, Brock WE. Ultrastructure of anaplasmal inclusions (Pawhuska isolate) and their appendages in intact and hemolyzed erythrocytes and in complement-fixation antigen.. Am J Vet Res 1978 Jul;39(7):1123-30.
- Ristic M, Holland CJ, Dawson JE, Sessions J, Palmer J. Diagnosis of equine monocytic ehrlichiosis (Potomac horse fever) by indirect immunofluorescence.. J Am Vet Med Assoc 1986 Jul 1;189(1):39-46.
- Ristic M, Dawson J, Holland CJ, Jenny A. Susceptibility of dogs to infection with Ehrlichia risticii, causative agent of equine monocytic ehrlichiosis (Potomac horse fever).. Am J Vet Res 1988 Sep;49(9):1497-500.
- Magnarelli LA, Anderson JF, Philip RN, Burgdorfer W, Chappell WA. Rickettsiae-infected ticks (acari: Ixodidae) and seropositive mammals at a focus for Rocky Mountain spotted fever in Connecticut, USA.. J Med Entomol 1983 Mar 30;20(2):151-6.
- Uilenberg G. Heartwater (Cowdria ruminantium infection): current status.. Adv Vet Sci Comp Med 1983;27:427-80.
- Rikihisa Y, Johnson GC, Burger CJ. Reduced immune responsiveness and lymphoid depletion in mice infected with Ehrlichia risticii.. Infect Immun 1987 Sep;55(9):2215-22.
- Rikihisa Y, Perry B, Cordes D. Rickettsial link with acute equine diarrhoea.. Vet Rec 1984 Oct 13;115(15):390.
- Perry BD, Schmidtmann ET, Rice RM, Hansen JW, Fletcher M, Turner EC, Robl MG, Hahn NE. Epidemiology of Potomac horse fever: an investigation into the possible role of non-equine mammals.. Vet Rec 1989 Jul 22;125(4):83-6.
- Burgdorfer W. A review of Rocky Mountain spotted fever (tick-borne typhus), its agent, and its tick vectors in the United States.. J Med Entomol 1975 Sep 25;12(3):269-78.
- Schmidtmann ET, Robl MG, Carroll JF. Attempted transmission of Ehrlichia risticii by field-captured Dermacentor variabilis (Acari: Ixodidae).. Am J Vet Res 1986 Nov;47(11):2393-5.
- Rikihisa Y, Perry BD. Causative ehrlichial organisms in Potomac horse fever.. Infect Immun 1985 Sep;49(3):513-7.
- Oaks SC Jr, Osterman JV, Hetrick FM. Plaque assay and cloning of scrub typhus rickettsiae in irradiated L-929 cells.. J Clin Microbiol 1977 Jul;6(1):76-80.
- Jenkins SJ, Jones NK, Jenny AL. Potomac horse fever agent in mice.. Vet Rec 1985 Nov 23;117(21):556-7.
- . Causative agent of Potomac horse fever.. Vet Rec 1984 Nov 24;115(21):554-5.
Citations
This article has been cited 3 times.- Pusterla N, Madigan JE, Chae JS, DeRock E, Johnson E, Pusterla JB. Helminthic transmission and isolation of Ehrlichia risticii, the causative agent of Potomac horse fever, by using trematode stages from freshwater stream snails.. J Clin Microbiol 2000 Mar;38(3):1293-7.
- Barlough JE, Reubel GH, Madigan JE, Vredevoe LK, Miller PE, Rikihisa Y. Detection of Ehrlichia risticii, the agent of Potomac horse fever, in freshwater stream snails (Pleuroceridae: Juga spp.) from northern California.. Appl Environ Microbiol 1998 Aug;64(8):2888-93.
- Reubel GH, Barlough JE, Madigan JE. Production and characterization of Ehrlichia risticii, the agent of Potomac horse fever, from snails (Pleuroceridae: Juga spp.) in aquarium culture and genetic comparison to equine strains.. J Clin Microbiol 1998 Jun;36(6):1501-11.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
