A protozoan parasite (malaria–like) of the blood that causes a hemolytic disease known as Babesiosis.
Genus of protozoa of the family Babesiidae that causes babesiosis, a febrile illness that causes symptoms similar to those found in influenza, accompanied by hemolytic anemia. Babesia microti is the principal human pathogen, transmitted to humans by tick bite. Other hosts include cattle, sheep, horses, and dogs.