• Babesiosis


    Babesiosis is an infection that damages the red blood cells. Red blood cells travel in the blood and carry oxygen throughout the body. Damage to a large number of these cells can decrease the level of oxygen in the blood.
    Mild babesiosis may not cause symptoms. Severe illness can lead to serious and life threatening problems because of the destruction of red blood cells.


    Babesiosis is caused by a Babesia parasite. It is most often passed to humans through a bite from an infected tick.
    Rarely, the parasite can be passed through a blood transfusion from an infected donor.
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    A Tick
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    Risk Factors

    Spending time in an area where ticks are common, increase your risk of infection. This includes outdoor areas with high grass or bushes. Not all tick bites will lead to infections.
    The risk of a severe infection is increased in certain people including:
    • Elderly
    • People with impaired immune systems (such as HIV or cancer)
    • People with liver disease
    • People with kidney disease
    • People who have had spleen removed or spleen is not working


    Many people will have no symptoms. Symptoms that do develop may not show up until a few days or weeks after the bite. They are often flu-like symptoms such as:
    • Fever
    • Chills
    • Sweating
    • Muscle and joint aches
    • Nausea and loss of appetite
    • Headaches
    • Fatigue
    A severe infection can cause difficulty breathing. It can also lead to complications with heart, liver or kidney.


    Your doctor will ask about your symptoms and medical history. The ticks that spread this infection tend to be very small. You may not have known you were bitten. The doctor may ask if you have spent time in areas known for ticks. A physical exam will be done.
    A blood test can confirm the presence of the infection and any other infection that may have been passed from the tick. Blood tests may also be done to look for damage to other organs such as the kidneys or liver. Your doctor may also test for other tick-related infections such as Lyme disease, ehrlichiosis, or anaplasmosis.


    Infections without symptoms usually do not require treatment. Your immune system is able to clear the parasite.
    An infection that causes symptoms may be treated with a combination of antibiotic and antiparasitic medications.
    Severe infections can lead to very low levels of red blood cells. This is a condition known as hemolytic anemia. This may require a hospital stay, blood transfusions, and other supportive care until the infection can be cleared.
    With this infection, it may be some time before the parasite is completely cleared.
    Do no donate blood until your doctor has said it is OK to do so. If you donated blood just before your diagnosis, let your doctor know.


    Avoiding tick bites is the best way to avoid babesiosis. Learn when ticks are most active in your area. Avoid tall grass, woods, and brush during these times. If you are in these areas:
    • Wear light colored clothing to make ticks easier to see.
    • Wear long pants and socks. Consider tucking your pants into your socks so the ticks have a harder time getting to your skin.
    • Use a bug repellant that contains DEET. Follow directions for use on container.
    After being outdoors:
    • Check yourself and your pets thoroughly for ticks.
    • Quickly remove any ticks that you have found.
    • If a tick is attached to the skin, remove it as soon as possible. Grab the tick close to your skin and pull out with steady pressure. Wash the area where the tick was attached with soap and water.
    It may take at least 24 hours for the parasite 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 a rash or symptoms.


    Centers for Disease Control and Prevention http://www.cdc.gov

    American Academy of Family Physicians http://familydoctor.org


    Communicable Disease Control http://www.gov.mb.ca

    Public Health Agency of Canada http://www.phac-aspc.gc.ca


    Babesiosis. American Academy of Family Physicians website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/babesiosis.html. Updated January 2010. Accessed September 4, 2013.

    Babesiosis. Centers for Disease Control and Prevention (CDC) website. Available at: http://www.cdc.gov/parasites/babesiosis/gen%5Finfo/index.html. Updated July 10, 2012. Accessed September 4, 2013.

    Babesiosis. National Institute of Allergy and Infectious Diseases website. Available at: http://www.niaid.nih.gov/topics/babesiosis/Pages/default.aspx. Updated November 12, 2012. Accessed September 4, 2013.

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