relapsing fever

American  

noun

Pathology.

1. one of a group of fevers characterized by relapses, occurring in many tropical countries, and caused by several species of spirochetes transmitted by several species of lice and ticks.

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relapsing fever British  

noun

1. Also called: recurrent fever.  any of various infectious diseases characterized by recurring fever, caused by the bite of body lice or ticks infected with spirochaetes of the genus Borrelia

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Etymology

Origin of relapsing fever

First recorded in 1840–50

Example Sentences

See Examples For:

relapsing fever

This allowed them to identify traces of several pathogens, including Yersinia pestis, the bacterium responsible for plague, and Borrelia recurrentis, which causes louse borne relapsing fever.

From Science Daily ● Jul. 8, 2026

This approach revealed traces of ancient pathogens, including the plague bacterium Yersinia pestis and the organism responsible for louse-borne relapsing fever, Borrelia recurrentis.

From Science Daily ● Apr. 22, 2026

But these soft ticks now seem to be surprisingly free of the harmful pathogen, which causes a sometimes-fatal relapsing fever.

From Slate ● Jun. 27, 2017

Finally, after poring over my lab results from an infectious-disease doctor, I noticed something she had ignored: a past infection for tick-borne relapsing fever and Colorado tick fever.

From New York Times ● Feb. 20, 2015

This spiro-bacterium was first observed in relapsing fever by Obermeier7 in 1873, and has since been identified as a spirillum or spiroechete.

From A System of Practical Medicine by American Authors, Vol. I Volume 1: Pathology and General Diseases by Various