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Ehrlichiosis

Ehrlichiosis is the general name used to describe several bacterial diseases that affect animals and humans. Human ehrlichiosisis a disease caused by at least three different ehrlichial species in the United States: Ehrlichia chaffeensis, Ehrlichia ewingii, and a third Ehrlichia species provisionally called Ehrlichia muris-like (EML). Ehrlichiae are transmitted to humans by the bite of an infected tick. The lone star tick (Amblyomma americanum) is the primary vector of both Ehrlichia chaffeensis and Ehrlichia ewingii in the United States. Typical symptoms include: fever, headache, fatigue, and muscle aches. Usually, these symptoms occur within 1-2 weeks following a tick bite. Ehrlichios is diagnosed based on symptoms, clinical presentation, and later confirmed with specialized laboratory tests. The first line treatment for adults and children of all ages is doxycycline.  Ehrlichiosis and other tickborne diseases can be prevented.

Ehrlichiosis Topics

blood smear
Symptoms, Diagnosis, and Treatment

Signs of illness, what to expect from your physician…

pie chart
Statistics and Epidemiology

Incidence, Geography, seasonality, and more…

microscope
In-Depth Information

Guidelines and Recommendations…

Related Tick Topics

woman spraying tick repellant on her arm
Avoiding Ticks

Avoid getting infected…
On CDC's Ticks website

people, deer, fox
Tick Lifecycle and Hosts

How ticks spread disease…
On CDC's Ticks website

removing a tick from the skin with tweezers
Removing a Tick

How to remove a tick…
On CDC's Ticks website

tick on a blade of grass
Other Diseases Caused by Ticks

Learn more about other tickborne diseases that can affect your health…
On CDC's Ticks website

 
Contact Us:
  • Centers for Disease Control and Prevention
    Rickettsial Zoonoses Branch
    Mail Stop G-44
    1600 Clifton Rd
    Atlanta, GA 30333
  • 800-CDC-INFO
    (800-232-4636)
    TTY: (888) 232-6348
  • Contact CDC–INFO
USA.gov: The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Rd. Atlanta, GA 30333, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO
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