ehr·​lich·​i·​o·​sis | \ er-ˌli-kē-ˈō-sis How to pronounce ehrlichiosis (audio) \
plural ehrlichioses\ er-​ˌli-​kē-​ˈō-​ˌsēz How to pronounce ehrlichioses (audio) \

Definition of ehrlichiosis

: infection with or disease caused by tick-borne bacteria (genus Ehrlichia of the family Anaplasmataceae)

Examples of ehrlichiosis in a Sentence

Recent Examples on the Web Cases of Lyme disease, Powassan virus; spotted fever rickettsiosis, including Rocky Mountain spotted fever, anaplasmosis, ehrlichiosis, babesiosis and tularemia all increased last year. Ashley Welch, CBS News, "Diseases spread by ticks hit record level in U.S.," 14 Nov. 2018 With a wetter and warmer climate, Lyme disease and ehrlichiosis could become more common as the number of tick bites increase. David Crawshaw, Washington Post, "Angry birds: Swooping Australian magpie causes fatal cyclist crash," 18 Sep. 2019 The tick population rises in turn, increasing the spread of diseases such as Lyme or ehrlichiosis. Natasha Frost, Quartz, "Climate change is also terrible for your ragweed allergy," 2 Sep. 2019 Blood testing can help diagnose both anaplasmosis and ehrlichiosis, and both can also be treated with antibiotics. Patia Braithwaite, SELF, "8 Tick-Borne Illnesses That Aren’t Lyme Disease," 26 July 2019 These include Lyme disease, Zika virus, ehrlichiosis, and others. Dipesh Navsaria, Houston Chronicle, "What parents should know to prevent — and deal with — bug bites," 6 July 2018 Last year, Mainers reported 20 cases of ehrlichiosis, a bacterial illness that can cause flu-like symptoms and difficulty breathing, up from just four cases the year before. Thomas Leavy, CBS News, "Maine on the lookout for ticks that cause red-meat allergy," 25 June 2018 Cases of Lyme, Rocky Mountain spotted fever, babesiosis, anaplasmosis and ehrlichiosis have increased several times over. Joyce Sakamoto, Washington Post, "Ticks and mosquitoes are ready to deliver disease in a bite, but you can stop them," 18 June 2018 One of the new diseases is a variant of ehrlichiosis, the infection Slone suffered. Elizabeth Cohen, CNN, "Survivor of near-fatal tick bite has a lesson for summer," 25 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ehrlichiosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ehrlichiosis

1965, in the meaning defined above

History and Etymology for ehrlichiosis

New Latin, from Ehrlichia, bacteria genus, from Paul Ehrlich

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The first known use of ehrlichiosis was in 1965

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Cite this Entry

“Ehrlichiosis.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2020.

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More Definitions for ehrlichiosis


ehr·​lich·​i·​o·​sis | \ er-ˌlik-ē-ˈō-sis How to pronounce ehrlichiosis (audio) \
plural ehrlichioses\ -​ˌsēz How to pronounce ehrlichioses (audio) \

Medical Definition of ehrlichiosis

: infection with or a disease caused by tick-borne bacteria of the genus Ehrlichia that affects both humans and animals (such as dogs, horses, and sheep) and that in humans is marked especially by fever, headache, chills, muscle aches, and fatigue

Note: When ehrlichiosis occurs in humans, the disease is often referred to as human granulocytic ehrlichiosis or human monocytic ehrlichiosis depending on the type of white blood cell (granulocyte or monocyte) infected. Following reclassification of the causative agent of human granulocytic ehrlichiosis to the genus Anaplasma, human granulocytic ehrlichiosis is now also called human granulocytic anaplasmosis or simply, anaplasmosis.

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