Babesia microti, Babesia duncani (WA1) and Babesia sp. (MO1) are obligate intra-erythrocytic protozoans transmitted by tick vectors, causing flu-like symptoms as well as a malaria-like illness. All three agents can be transmitted by blood donor units from asymptomatic donors, but Babesia microti has caused the most clinical problems in this area.
As the demand for Babesia sp. (MO1) has been underwhelming (!!), we suggest IFA slides made with Babesia divergens, which is highly crossreactive and immediately available in our Inventory.
All of these antigens, including Babesia microti IFA slide antigen, are propagated in vitro using human type O erythrocytes to produce the most sensitive and specific test possible.
Special note on the use of Babesia duncani (WA1) IFA: Our manuscript is in preparation for the use of these B. duncani IFA slides for detection of recent tick bites in humans and dogs. Screening sera at 1:64 detects recent tick bites in both IgG and IgM class antibody, although the tick may not have been infected. Strong reactivity related to actual B.duncani infection is rare, with less than 1 reported case per year since this species was identified in 1991. Information available by phone or email prior to publication.