Quantitative evaluation of ehrlichial burden in horses after experimental transmission of human granulocytic Ehrlichia agent by intravenous inoculation with infected leukocytes and by infected ticks.
Abstract: This paper describes the kinetics of the human granulocytic ehrlichiosis agent in the blood of horses experimentally infected by intravenous inoculation with infected leukocytes and by infected ticks as evaluated by using a real-time quantitative PCR assay. The data obtained indicated differences in the period of incubation, duration of rickettsemia, and initial and maximal ehrlichial loads between the two routes of infection.
Publication Date: 1999-11-24 PubMed ID: 10565928PubMed Central: PMC85876DOI: 10.1128/JCM.37.12.4042-4044.1999Google 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
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The study examines the behavior of the bacteria causing human granulocytic ehrlichiosis in horses. It does this by testing two methods of infection: through infected white blood cells and through tick bites, then comparing the differences in infection progression.
Understanding Human Granulocytic Ehrlichiosis
- Ehrlichiosis, in this case human granulocytic ehrlichiosis, is an infectious disease caused by bacteria of the Ehrlichia genus.
- These bacteria are typically transmitted via tick bites and are pathogenic to both humans and animals, including horses.
- In terms of symptoms and impact on host health, it can range from mild to potentially life-threatening.
Experimental Transmission of Ehrlichiosis
- The researchers in this study experimented with two methods of transmitting the ehrlichiosis-causing agent.
- One was direct injection of infected leukocytes (white blood cells) via the intravenous route, effectively bypassing the typical route of transmission (tick bites).
- The other method was via the ‘natural’ route, that is, through tick bites.
Monitoring the Infection & Results
- Following the initiation of infection, the researchers closely monitored various parameters to understand the progression of the disease.
- This included the period of incubation (how long from infection to first symptoms), the length of rickettsemia (presence of bacteria in the blood), and the initial and peak loads of the ehrlichial bacteria in the blood.
- The whole process was assessed with the help of real-time quantitative PCR, a tool that allows the quantification of specific DNA or RNA molecules, including those of the bacteria responsible for ehrlichiosis.
- The results showed differences in all monitored parameters between the two modes of infection, indicating that the route of transmission could have effects on the progression of the disease.
Cite This Article
APA
Pusterla N, Leutenegger CM, Chae JS, Lutz H, Kimsey RB, Dumler JS, Madigan JE.
(1999).
Quantitative evaluation of ehrlichial burden in horses after experimental transmission of human granulocytic Ehrlichia agent by intravenous inoculation with infected leukocytes and by infected ticks.
J Clin Microbiol, 37(12), 4042-4044.
https://doi.org/10.1128/JCM.37.12.4042-4044.1999 Publication
Researcher Affiliations
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California 95616, USA. npusterla@ucdavis.edu
MeSH Terms
- Animals
- Colony Count, Microbial
- DNA, Bacterial / blood
- Ehrlichia / genetics
- Ehrlichia / isolation & purification
- Ehrlichia / physiology
- Ehrlichiosis / microbiology
- Ehrlichiosis / transmission
- Ehrlichiosis / veterinary
- Horse Diseases / microbiology
- Horse Diseases / pathology
- Horse Diseases / transmission
- Horses
- Humans
- Ixodes / microbiology
- Leukocytes / microbiology
- Polymerase Chain Reaction / methods
Grant Funding
- A14213 / PHS HHS
References
This article includes 19 references
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