Ehrlichiosis is an infection passed through a tick bite. It can be treated with medication, but can be fatal if left untreated.
Ehrlichiosis is cause by specific bacteria. The bacteria are passed through the bite of a tick, specifically the lonestar tick, deer tick, and dog tick.
Spending time in an area where ticks are common, increases your risk of infection. This includes outdoor areas with high grass or bushes. Not all tick bites will lead to infection.
The infection is most often found in the mid-Atlantic, southeastern, and south central United States.
The risk of a severe infection is increased in people with impaired immune systems such as HIV or cancer.
It may take at least 1-2 weeks before symptoms develop. The first symptoms are often flu-like symptoms such as:
Some may also develop:
Some people also develop a rash.
An untreated infection can cause difficulty breathing and bleeding problems.
You will be asked about your symptoms and medical history. You may not have known you were bitten. You may not have a bite mark. You may be asked if you have spent time in areas known for ticks. A physical exam will be done.
A blood test may be done to:
Ehrlichiosis can be successfully treated with antibiotics.
Other medications may be advised to help relieve symptoms until the infection has cleared. It may take a few weeks before all of the symptoms have gone away completely.
Avoiding tick bites is the best way to prevent ehrlichiosis. Learn when ticks are most active in your area. Avoid tall grass, woods, and brush during these times. If you are in these areas:
After being outdoors:
It may take at least 24 hours for the infection to pass through the bite. Not all tick bites will cause an infection. If you were bitten by a tick, watch the area over the next few days. Call your doctor if you develop any symptoms.
Centers for Disease Control and Prevention
Family Doctor—American Academy of Family Physicians
Public Health Agency of Canada
Ehrlichiosis. American Academy of Family Physicians website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/ehrlichiosis.html. Updated February 2014. Accessed September 23, 2014.
Ehrlichiosis. Centers for Disease Control and Prevention (CDC) website. Available at: http://www.cdc.gov/ehrlichiosis. Updated November 15, 2013. Accessed September 23, 2014.
Ehrlichiosis and anaplasmosis. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated August 7, 2014. Accessed September 23, 2014.
Ehrlichiosis and anaplasmosis. National Institute of Allergy and Infectious Diseases website. Available at: http://www.niaid.nih.gov/topics/ehrlichiosisanaplasmosis/Pages/Default.aspx. Accessed September 23, 2014.
Last reviewed September 2015 by James Cornell, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.