title: Serologic screening of United States blood donors for Babesia microti using an investigational enzyme immunoassay.
abstract: The tick-borne pathogen Babesia microti has become recognized as the leading infectious risk associated with blood transfusion in the United States, yet no Food and Drug Administration-licensed screening tests are currently available to mitigate this risk. The aim of this study was to evaluate the performance of an investigational enzyme immunoassay (EIA) for B. microti as a screening test applied to endemic and nonendemic blood donor populations.
  
  
  
  The study aimed to test 20,000 blood donors from areas of the United States considered endemic for B. microti and 10,000 donors from a nonendemic area with the investigational B. microti EIA. Repeat-reactive samples were retested by polymerase chain reaction (PCR), blood smear, immunofluorescent assay (IFA), and immunoblot assay. In parallel, serum samples from symptomatic patients with confirmed babesiosis were tested by EIA, IFA, and immunoblot assays.
  
  
  
  A total of 38 of 13,757 (0.28%) of the donors from New York, 7 of 4583 (0.15%) from Minnesota, and 11 of 8363 (0.13%) from New Mexico were found repeat reactive by EIA. Nine of the 56 EIA repeat-reactive donors (eight from New York and one from Minnesota) were positive by PCR. The specificity of the assay in a nonendemic population was 99.93%. Among IFA-positive clinical babesiosis patients, the sensitivity of the assay was 91.1%.
  
  
  
  The B. microti EIA detected PCR-positive, potentially infectious blood donors in an endemic population and exhibited high specificity among uninfected and unexposed individuals. The EIA promises to provide an effective tool for blood donor screening for B. microti in a format amenable to high-throughput and cost-effective screening.
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Levin
authors.affiliation: Creative Testing Solutions, Tempe, Arizona.
authors.forename: Phillip C
authors.initials: PC
authors.lastname: Williamson
authors.affiliation: Blood Systems Research Institute, San Francisco, California.|Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Evan M
authors.initials: EM
authors.lastname: Bloch
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: Joan
authors.initials: J
authors.lastname: Clifford
authors.affiliation: Creative Testing Solutions, Tempe, Arizona.
authors.forename: Sherri
authors.initials: S
authors.lastname: Cyrus
authors.affiliation: New York Blood Center, New York, New York.
authors.forename: Beth H
authors.initials: BH
authors.lastname: Shaz
authors.affiliation: New York Blood Center, New York, New York.
authors.forename: Debra
authors.initials: D
authors.lastname: Kessler
authors.affiliation: Innovative Blood Resources/Memorial Blood Centers, St Paul, Minnesota.
authors.forename: Jed
authors.initials: J
authors.lastname: Gorlin
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: James L
authors.initials: JL
authors.lastname: Erwin
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: Neil X
authors.initials: NX
authors.lastname: Krueger
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: Greg V
authors.initials: GV
authors.lastname: Williams
authors.affiliation: Immunetics, Inc., Boston, Massachusetts.
authors.forename: Oksana
authors.initials: O
authors.lastname: Penezina
authors.affiliation: Tufts University Cummings School of Veterinary Medicine, North Grafton, Massachusetts.
authors.forename: Sam R
authors.initials: SR
authors.lastname: Telford
authors.affiliation: Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: John A
authors.initials: JA
authors.lastname: Branda
authors.affiliation: Yale School of Public Health and Yale School of Medicine, New Haven, Connecticut.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Krause
authors.affiliation: New York Medical College, Valhalla, New York.
authors.forename: Gary P
authors.initials: GP
authors.lastname: Wormser
authors.affiliation: Marshfield Clinic, Marshfield, Wisconsin.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Schotthoefer
authors.affiliation: Marshfield Clinic, Marshfield, Wisconsin.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Fritsche
authors.affiliation: Blood Systems Research Institute, San Francisco, California.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Busch
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D041001:Babesia microti / Q000302:isolation & purification*; D001404:Babesiosis / Q000097:blood / Q000453:epidemiology; D001782:Blood Donors; D019353:Endemic Diseases; D005260:Female; D057166:High-Throughput Screening Assays; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods* / Q000592:standards; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D012698:Serologic Tests / Q000379:methods*; D014481:United States; D055815:Young Adult