Babesiosis
What is babesiosis? Babesiosis is caused by microscopic parasites that infect red blood cells. Many different species (types) of Babesia parasites have been found in animals, only a few of which have been found in people. Babesia microti—which usually infects white-footed mice and other small mammals—is the main species that has been found in people in the United States. Occasional cases caused by other Babesia species have been detected. How do people get infected with Babesia? The main way is through the bite of an infected tick: Babesia microti is spread by Ixodes scapularis ticks, which are commonly called blacklegged ticks or deer ticks. (Although white-tailed deer are the most important food source for the adult stage of the tick, deer are not infected with B. microti.) The parasite typically is spread by the young nymph stage of the tick. Nymphs are most apt to be found during warm months in areas with woods, brush, or grass. Infected people might not recall a tick bite because I. scapularis nymphs are very small (about the size of a poppy seed). Other possible ways of becoming infected with Babesia include: receipt of a contaminated blood transfusion (no tests have been licensed yet for donor screening); or transmission from an infected mother to her baby during pregnancy or delivery. It burrows into RBCs and multiplies inside before destroying it. Patient will experience fevers, fatigue, pain, splenomegaly.
