Babesiosis Fact Sheet
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- Babesiosis is caused by a microscopic parasite known as Babesia.
- Babesia parasites infect the red blood cells.
- The most common cause of babesiosis in humans in the Unites States is Babesia microti.
- In the United States, babesiosis most commonly occurs in the Northeast and upper Midwest.
Babesiosis is transmitted in nature by the bite of infected ticks
- Ixodes scapularis, also called the blacklegged (or deer) tick, transmits the infection in nature.
- I.scapularis can also transmit the bacteria that cause Lyme disease and anaplasmosis.
- Transmission can also occur in blood products such as blood transfusions.
Some, but not all, people with babesiosis develop symptoms
- When symptoms do occur, they usually appear 1 week to a few months after a tick bite.
- Some people develop nonspecific flu-like symptoms, such as fever, chills, sweats, headache, body aches, loss of appetite, nausea, or fatigue.
- Because Babesia parasites infect and destroy red blood cells, babesiosis can cause hemolytic anemia.
- Complications can occur and disease is most severe for the elderly, for individuals who are immunocompromised, and for those without a spleen.
Diagnosis and treatment
- The Babesia parasites can be seen in blood viewed under a microscope.
- There are other blood tests that can help diagnose babesiosis.
- See your doctor right away if you think you might have babesiosis.
- For ill patients, babesiosis usually is treated for at least 7-10 days with a combination of 2 drugs.
- Make sure you inform your doctor of any recent tick bites.
Keep Ticks Off
- Ticks are most active from late spring through early fall.
- Insect repellent containing 20-30% DEET is recommended to prevent tick bites.
- Repellents with up to 30% DEET can safely be used on children over 2 months of age.
- Treat clothes with permethrin (don't use permethrin directly on skin).
- Long pants and long sleeves help keep ticks off of skin, and tucking pant legs into socks and shirts into pants keeps ticks on outside of clothing.
- Light colored clothing lets you spot ticks more easily.
- Talk to your veterinarian about tick control products for your pets.
- When enjoying the outdoors, be aware that wooded or brushy areas with tall grass and leaf litter are prime tick habitat. Walk in the center of the trail.
- Check yoruself, your kids and your pets daily for ticks when spending time in tick habitat.
- Bathe or shower as soon as possible after coming indoors (within 2 hours) to wash off ticks.
To Remove Ticks
- Use fine-tipped tweezers.
- Grab the tick close to the skin; do not twist or jerk the tick.
- Gently pull straight up until all parts of the tick are removed.
- Wash your hands with soap and water or an alcohol-based rub.
- Clean the site of the tick bite with soap and water or an antiseptic.
- Do not use petroleum jelly, a hot match, nail polish, or other products to remove ticks.
For more information on tickborne disease, visit: