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Babesiosis: Treatment and prevention

Peter J Krause, MD
Edouard G Vannier, PhD
Section Editor
Johanna Daily, MD, MSc
Deputy Editor
Elinor L Baron, MD, DTMH


Babesiosis is an infectious disease caused by protozoa of the genus Babesia and is transmitted primarily by tick vectors. Transmission rarely occurs via blood transfusion, organ transplantation, and congenitally. Babesia protozoa invade and cause lysis of red blood cells in mammalian hosts [1-3].

Babesia microti is the primary agent of human babesiosis in the United States, particularly in the Northeast and upper Midwest where it is endemic. Nearly all cases in Europe have been attributed to Babesia divergens, but the infection is sporadic. Babesia venatorum is endemic in northeastern China.

The treatment and prevention of babesiosis will be reviewed here. The clinical manifestations, diagnosis, microbiology, epidemiology, and pathogenesis of babesiosis are discussed separately. (See "Babesiosis: Clinical manifestations and diagnosis" and "Babesiosis: Microbiology, epidemiology, and pathogenesis".)


Immunocompetent patients

Asymptomatic infection — Antimicrobial therapy should not be given to individuals with asymptomatic B. microti infection [4].

Mild to moderate disease — Mild to moderate babesiosis typically occurs in immunocompetent patients and is associated with parasitemia <4 percent; it does not require hospital admission. (See "Babesiosis: Clinical manifestations and diagnosis", section on 'Mild to moderate disease'.)

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Literature review current through: Nov 2017. | This topic last updated: Nov 13, 2017.
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