South Dakota Department of Health
Office of Disease Prevention - 605-773-3737 — (1-800-592-1861 in South Dakota only)
This material is provided for informational purposes only and is not a substitute
for medical care. We are not able to answer personal medical questions. Please see your
health care provider concerning appropriate care, treatment or other medical advice.
What is babesiosis?
Babesiosis is a rare, severe and sometimes fatal tick-borne disease caused by an infection with a red blood cell parasite.
Who gets babesiosis?
Babesiosis is seen most frequently in the elderly or in immunocompromised individuals. Cases of this disease have been reported during springs, summer and fall in coastal areas in the northeastern United States. Cases have also been reported in Wisconsin, California, Georgia and some European countries. Several cases of babesiosis can occur in people who have had their spleen removed.
How is babesiosis spread?
Babesiosis is caused by Babesia mictroti, a parasite transmitted by the bite of an infected deer tick. The tick is carried by meadow voles, mice and deer. Transmission to humans generally occurs from the bite of the nymph, while the adult tick generally feeds on deer. Transmission can also occur via contaminated blood transfusions.
What are the symptoms of babesiosis?
The disease can cause fever, fatigue and hemolytic anemia lasting from several days to several months. Infections can occur without producing symptoms.
How soon do symptoms appear?
It may take from one to 12 months for symptoms to appear; less time for immunocompromised people.
Does past infection with babesiosis make a person immune?
It is not known whether past infection with babesiosis can make a person immune.
What is the treatment for babesiosis?
Standardized treatments for babesiosis have not been developed. However, some drugs used in the treatment of malaria have been found to be effective in a few patients with babesiosis.
What can be done to prevent the spread of babesiosis?
It is important to control rodents around human habitation and to use tick repellents. It is helpful to wear light colored clothing and to tuck pants into socks when walking through tick-infested areas.