A Fluorescence in Situ Hybridization (FISH) Test for Diagnosing Babesiosis.

Apicomplexan parasites of the genusBabesiacause babesiosis in humans and animals. The microscopic examination of stained blood smears, detection of serum antibodies by immunoassays, and PCR-based identification of parasite nucleic acid in blood are common laboratory methods for diagnosing babesiosis. The present study evaluated a commercially availableBabesiagenus-specific fluorescence in situ hybridization (FISH) test for detectingBabesiaparasites in blood smears. The FISH test detectedBabesia duncaniandBabesia microti, two common species that cause human infections in the USA, and otherBabesiaspecies of human and veterinary importance in less than two hours. TheBabesiagenus-specific FISH test supplements other existing laboratory methods for diagnosing babesiosis and may be particularly useful in resource-limited laboratories.