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Updated: Jun 19, 2026
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Cultivation Methods of Spirochetes from Borrelia burgdorferi Sensu Lato Complex and Relapsing Fever Borrelia
Published on: November 25, 2022
RELAPSE PHENOMENA OF SPIRONEMA RECURRENTIS
1Laboratory of Tropical Medicine, Department of Medicine, Peking Union Medical College, Peking, China.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Splenectomy in squirrels infected with Borrelia recurrentis led to relapses and the emergence of new spirochete strains. The spleen plays a role in preventing relapses but not in immune substance formation.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Immunology
Background:
- Relapsing fever is caused by Borrelia recurrentis spirochetes.
- The role of the spleen in the pathogenesis of relapsing fever and spirochete strain variation is not fully understood.
Purpose of the Study:
- To investigate the effect of splenectomy on Borrelia recurrentis infection in squirrels.
- To explore the potential for spirochete strain variation during relapses.
Main Methods:
- Squirrels and chipmunks were inoculated with Borrelia recurrentis.
- Splenectomy was performed on a subset of infected squirrels.
- Infected animals were monitored for infection intensity, relapses, and spirochete strain characteristics via agglutination.
Main Results:
- Splenectomized squirrels exhibited increased infection intensity and developed relapses, yielding up to six distinct spirochete strains.
- Normal squirrels experienced single infections without relapses.
- The spleen appears to protect against relapses but does not inhibit the formation of specific immune substances.
Conclusions:
- The spleen influences the clinical course of relapsing fever by preventing relapses.
- Spirochete strain variation occurs during relapses, suggesting a dynamic interaction between host and pathogen.
- Current evidence does not support the classification of Borrelia recurrentis into distinct species based on observed strain characteristics.
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