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What is ehrlichiosis?

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Ehrlichiosis

Ehrlichiosis is the general name for a group of diseases caused by bacteria of the genus Ehrlichia. [1] In the United States, these diseases are caused by Ehrlichia chaffeensis, E. ewingii, and E. muris eauclairensis. [1]

Etiology

The causative bacteria are Ehrlichia chaffeensis, Ehrlichia ewingii, and Ehrlichia muris eauclairensis. [1]

Transmission

Ehrlichiosis is spread to humans primarily through the bite of infected ticks. [1] In the United States, E. chaffeensis and E. ewingii are carried by the lone star tick (Amblyomma americanum). [2] In the United States, E. muris eauclairensis is carried by the blacklegged tick (Ixodes scapularis). [2] Ehrlichiosis can also be spread in rare cases through blood transfusion and organ transplant. [2]

Timing and typical clinical presentation

Fever, chills, headache, and muscle aches can occur. [1] Symptoms begin about 1–2 weeks after a tick bite. [2]

Prevention

A vaccine to prevent ehrlichiosis is not available. [1] Prevention focuses on preventing tick bites and preventing ticks on pets and in yards. [1]

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