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

Their work uncovered traces of two disease-causing pathogens -- those behind paratyphoid fever and relapsing fever -- which match the symptoms described in eyewitness records from that time.

From Science Daily • Oct. 26, 2025

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

How many people died from influenza, typhus, relapsing fever, malaria, typhoid and smallpox was never recorded, but flu alone killed an estimated 16,000,000.

From Time Magazine Archive

From what has already been said, it will be anticipated that the variations of the temperature in relapsing fever constitute the most peculiar and characteristic feature of that disease.

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