History of Discovery
Epidemiology and
Country Information
Public Health and
Prevention Strategies

Image is of a primarily bovine form of babesiosis,
but notice the same characteristic tetrads explained here.

Texas cattle tick fever, prioplasmosis, tick fever, red water and tristesa
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Babesia was first defined as a clinical entity by Babes in 1888 when he was investigating the cause of death of 30,000 to 50,000 cows in Romania.

The disease was first described in 1893 by Smith and Kilborne as a tick-transmitted disease of cattle, characterized by anemia, fever, and hemoglobinuria.

The first human case was described in 1957 in a previously splenectomized Yugoslavian farmer who entered a hospital with fever, anemia, jaundice, and hemoglobinuria. Based on the clinical constellation and the fact that his blood contained numerous intraerythrocytic "rings," he was misdiagnosed as having malaria. The patient died 8 days later and a subsequent review of the slides revealed that the infecting parasite was in fact Babesia.

Interest in the United States increased with the report in 1977 of 5 cases of Babesia microti infection in less than 3 months on the island of Nantucket, Massachusetts.
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Distribution of B. bovis.
While Babesia infections in animals, B. bovis, are distributed globally, B. microti infections occur mainly in coastal areas in the northeastern United States, especially the offshore islands of New York, Rhode Island and Massachusetts; and the nearby mainland, including Connecticut. Cases have also been reported from Wisconsin, Minnesota, Virginia, Maryland, Georgia, and Mexico. Babesia isolates from patients in Washington and California have been characterized as WA-1-type parasites, which are genetically and antigenically distinct from B. microti. Yet another strain has been isolated in Missouri. In Europe, B. divergens has been responsible for most cases of babesiosis; most of these infections were in Yugoslavia, Russia, France, the United Kingdom, and Ireland.
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No vaccine is available to protect humans against babesiosis.
Prevention of babesiosis involves avoidance of tick-infested areas, use of protective clothing and insect repellents, and a careful search for and removal of ticks.

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Babesiosis image from
B. bovis distrubition image from html/exoticas/bb.htm

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