Reports on HIV/AIDS: 1990

NOVEMBER 23, 1990, MMWR, Vol. 39, No. 46, pp. 829-831
TABLE 1. Results of HIV-2 enzyme immunoassay (EIA) testing of serum repeatedly
reactive by the HIV-1 EIA, by initial HIV-1 Western blot result - American Red Cross
Blood Services, January 1987-December 1989
HIV-2 EIA
Repeatedly Not repeatedly
HIV-1 reactive reactive* Nonreactive Total
Western blot No. (%) No. (%) No. (%) No. (%)
Positive 2,085 ( 86) 132 ( 47) 993 ( 4) 3,210 ( 13)
Indeterminate 185 ( 8) 49 ( 18) 3,729 ( 17) 3,963 ( 16)
Negative 156 ( 6) 99 ( 35) 17,398 ( 79) 17,653 ( 71)
Total 2,426 (100) 280 (100) 22,120 (100) 24,826 (100)
*Initially reactive but not repeatedly reactive.
Editorial Note: ARCBS accounts for >50% of the blood donations in the United
States (4). Sixty percent to 90% of serum samples from persons with HIV-2 infection
are reactive by the Abbott whole-virus lysate HIV-1 EIA (1,2), which is used for donor
screening by the ARCBS. Therefore, by testing blood donations that were repeatedly
reactive by the HIV-1 EIA (approximately 0.13% of >18 million), the ARCBS study
would have detected >60% of donations potentially containing HIV-2 antibody.
However, among approximately 18 million ARCBS donations, no blood donors with
HIV-2 infection were detected.
A previously reported study from San Francisco that used a similar methodology
for 942 donor samples reactive by the HIV-1 EIA also failed to identify donors
seropositive for HIV-2 antibody (5). Although the San Francisco study and the study
reported here may have failed to detect persons with HIV-2 infection whose serum
samples did not cross-react on the HIV-1 EIA, these findings suggest that from 1987
through 1989, HIV-2 infection in U.S. blood donors was extremely rare. In a previous
study of 8503 blood donors randomly selected from three areas of the United States
in 1988, no donors with HIV-2 infection were detected (6).
Eighteen persons with HIV-2 infection in the United States have been reported to
CDC. All of the 15 for whom historical information is available had recently immigrated from West Africa, had sexual contact with West Africans, or had traveled to
West Africa. One person was a volunteer blood donor (7) who was born in the United
States and had traveled to West Africa; she donated blood in 1986 before the HIV-2
surveillance project began. Because she had a reactive HIV-1 EIA, her blood was not
transfused.
Based on the low prevalence of HIV-2 in the United States and the failure to detect
HIV-2 infections in large blood-donor surveys, routine HIV-2 donor screening with
HIV-2-specific assays from 1987 through 1989 would have detected few, if any,
additional donations from persons infected with HIV-2. For these reasons, the Blood
Products Advisory Committee of the FDA has recommended and the FDA has
determined that routine HIV-2 screening of blood and plasma donated for use in
transfusion is not necessary (8). (Moreover, recent immigrants from West Africa or
persons who are sexual contacts of West Africans have been requested to defer from
donating blood [9 ].) FDA will reevaluate and update the recommendations for donor
deferral and screening of blood donors for HIV-2 based on additional surveillance
reports and new technologic developments, such as licensed combination tests for
the detection of antibodies to both HIV-1 and HIV-2. CDC and collaborating blood
collection agencies will continue surveillance for HIV-2 in U.S. blood donors and other
selected populations.

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