Ehrlichiosis

Overview

Ehrlichiosis is a bacterial infection that infects and kills white blood cells. These obligately intracellular bacteria are members of the family Anaplasmataceae, genera Ehrlichia and Anaplasma.

Symptoms

Symptoms may seem like the flu (influenza), and may include: * Chills * Fever * Headache * Muscle aches * Nausea

Causes

Ehrlichiosis is caused by bacteria that belong to the family called Rickettsiae. Rickettsial bacteria cause a number of serious diseases worldwide, including Rocky Mountain spotted fever and typhus. All of these diseases are spread to humans by a tick, flea, or mite bite. Scientists first described ehrlichiosis in 1990, and have identified two types in the United States: * Human monocytic ehrlichiosis (HME) is caused by the rickettsial bacteria called Ehrlichia chaffeensis. * Human granulocytic ehrlichiosis (HGE) is also called human granulocytic anaplasmosis (HGA). It is caused by the rickettsial bacteria called Anaplasma phagocytophilum (once called Ehrlichia equi or Ehrlichia phagocytophila). Ehrlichia bacteria can be carried by the Lone Star tick, the American dog tick, and the deer tick, which can also cause Lyme disease.

Prevention

Ehrlichiosis is spread by tick bites. Preventing tick bites will prevent this condition, as well as other tick-borne diseases. Common measures include: * Avoiding dense brush and long grasses when hiking * Checking yourself for ticks and removing any that you find after being outside * Not standing under trees or bushes * Using insect repellent * Wearing clothing to cover skin

Prognosis

Ehrlichiosis is rarely deadly. With antibiotics, patients usually improve within 24 - 48 hours. Recovery takes 3 weeks.

Treatment

Antibiotics (tetracycline or doxycycline) are used to treat the disease. Young children should not take tetracycline by mouth until after all their permanent teeth have grown in, because it can permanently discolor growing teeth.