Human T-cell leukemia virus type II infection frequently goes undetected in contemporary US blood donors.
Serologic screening for human T-cell leukemia virus type I (HTLV-I) infection was begun in US blood banks with the licensure of enzyme-linked immunosorbent assays (ELISA) in December 1988. We examined the donation histories of the first 60 Western blot (WB)-confirmed HTLV-I/II positive donors to one blood center and found 8 had made 16 previous donations that scored negative on the screening ELISA. All 16 donations had ELISA absorbance below the cutoff for a positive assay, but still well above that of the average donation (17.6% +/- 5.7% of the cutoff). In a more extensive study, 17 donations from a total of 61,752 at six blood centers were both ELISA-positive and WB-positive for HTLV-I (4) or HTLV-II (13), and 218 samples had ELISA absorbance greater than 50% of the ELISA cutoff. One hundred seventy-eight of the 218 were tested further by WB and 11 were found positive. All 11 positives were confirmed by polymerase chain reaction; 10 had HTLV-II and 1 had HTLV-I. Thus, the HTLV-I-based screening ELISA missed at least 10 of 23, or 43% (95% confidence interval, 23% to 66%), of HTLV-II infections, compared with 1 of 5, or 20%, of HTLV-I infections.
Hjelle
B
B
Department of Pathology, University of New Mexico School of Medicine, Albuquerque 87131.
Wilson
C
C
Cyrus
S
S
Bradshaw
P
P
Lo
J
J
Schammel
C
C
Wiltbank
T
T
Alexander
S
S
D001782:Blood Donors; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015481:HTLV-I Antibodies / Q000097:blood; D015482:HTLV-II Antibodies / Q000097:blood*; D015491:HTLV-II Infections / Q000175:diagnosis*; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D014481:United States
D015481:HTLV-I Antibodies; D015482:HTLV-II Antibodies