relapsing fever


Definition of relapsing fever

: a variable acute epidemic disease that is marked by recurring high fever usually lasting three to seven days and is caused by a spirochete (genus Borrelia) transmitted by the bites of lice and ticks

First Known Use of relapsing fever

1828, in the meaning defined above

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The first known use of relapsing fever was in 1828

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Cite this Entry

“Relapsing fever.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2020.

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relapsing fever


Medical Definition of relapsing fever

: a variable acute infectious disease that is marked by sudden recurring episodes of high fever which usually last from three to seven days, are typically accompanied by myalgia, arthralgia, headache, nausea, and chills, and often end in a crisis stage marked by a spike in fever followed by an afebrile period and that is caused by a spirochete of the genus Borrelia (as B. hermsii, B. parkerii, or B. recurrentis) that circulates in the blood and is transmitted by the bite of a body louse (Pediculus humanus humanus) or a tick of the genus Ornithodoros — see mianeh fever

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