Anticipating that blood tests for detecting AIDS virus antibodies
will be available this month, the Government has announced new
recommendations for screening donated blood and plasma.
The Public Health Service’s proposed approach covers blood
testing procedures, the appropriateness of repeat tests, and steps for
informing persons whose test results are positive. The agency counsels
physicians on what medical measures to use and advice to give for
patients who test positive. PHS’s suggestions include ways to
prevent further spread of the disease. It also stresses the need to
“These Public Health Service recommendations are an important
step forward in meeting our responsibility to the American people,”
said Health and Human Services Secretary Margaret Heckler during a
recent press conference. Federal health officials estimate that less
than 1 per cent of blood donors will have positive, confirmed results
showing the presence of antibodies to HTLV-III, the virus believed to
Heckler said it is particularly important to emphasize the
uncertainty of the link between positive test results and the
disease’s course. “All our scientific evidence to date
indicates that although many people may have been exposed to the AIDS
virus, only a few will actually become ill,” she pointed out.
At this writing, 7,981 people had been diagnosed as having AIDS,
and 3,819 had died. Fifty-six cases had occurred in hemophiliacs, and
106 were transfusion-related.
Last April, PHS researchers isolated HTLV-III, developed a
prototype antibody detection kit, and licensed five firms (Abbott
Laboratories, Du Pont/Biotech, Electro-Nucleonics, Litton Bionetics, and
Travenol-Genentech) to refine and mass-produce the test kits. By all
accounts, the companies’ efforts have proceeded smoothly, sticking
to hoped-for deadlines and encountering no scientifc surprises.
A recent Journal of the American Medical Association report by
researchers representing several institutions found that the test, in
trials, had spotted HTLV-III antibodies in 82 per cent of 88 patients
known to have AIDS. For another 16 per cent, results were borderline,
while 2 per cent of AIDS patients did not have antibodies. Meanwhile, U
per cent of 297 volunteer blood donors had the antibody, 6 per cent were
borderline, and 93 per cent negative.
The report concluded that the test is “highly specific and
sensitive for AIDS.”
Still, while the Science might be encouraging to some, others find
the imperfections in the test unsettling. At an American Blood
Commission conference shortly after Secretary Heckler’s public
praise for the near-ready kit, opinion appeared split over the PHS
recommendations for use and counseling.
Moreover, some within the gay community have urged a boycott of the
test. For example, in a recent USA Today op-ed piece, Rodger McFarlane,
executive director of the Gay Men’s Health Crisis, said the test is
“relatively cheap and fast,” but also “appears to be
Because most AIDS victims are gay, he claimed, the test will be
used “as a marker for homosexuality. There are at present no legal
protections guarding test results from health insurers, employers, or
even the Government itself.”
He added: “Nobody, least of all a gay man, should allow this
test to be done on his or her blood except as part of a research program
offering maximum protection of results, with the highest
confidentiality.” Noting also that no member of at-risk groups for
AIDS should donate blood, McFarlane warned, “Until other tests are
introduced, especially tests that confirm the presence of the virus
itself, the antibody test alone can only serve to darken forever the
life of anyone who tests positive.”
At this writing, HHS expected to be clearing “more than
one” of the test kits for commercial distribution by the end of
February. The department also planned to mail to the nation’s blood
banks a set of instructions elaborating on the PHS recommendations. A
separate special letter was to go out to all practicing physicians in
the United States with suggestions on care and follow-up for those who
may test positive.
The following are PHS-recommended procedures for the antibody
* Initial screening. Persons accepted as donors should be informed
that their blood or plasma will be tested for HTLV-III antibody.
Persons not wishing to have their blood tested must refrain from
donating. Donors should be told they will be notified if their test is
positive and that they may be placed on the collection agency’s
donor deferral list, as is currently done for other infectious diseases.
They should further be informed of other deferral lists to which
positive donors’ names may be added.
All blood or plasma should be tested for HTLV-III antibody by the
enzyme-linked immunosorbent assay (ELISA) test. Any blood or plasam
found positive on initial testing must not be transfused or manufactured
into other products capable of transmitting infectious agents. When
ELISA is used to screen populations in whom the prevalence of HTLV-III
infections is low, the proportion of positive results that are falsely
positive will be high. Therefore, the ELISA should be repeated on all
seropositive specimens before the donor is notified. If the repeat
ELISA test is negative, the specimen should be tested by another test.
* Other testing. Other tests have included immunofluorescence and
radioimmunoprecipitation assays. But the most extensive experience has
been with the Western blot technique, in which antibodies can be
detected to HTLV-III proteins of specific molecular weights. Based on
available data, the Western blot should be considered positive for
antibody to HTLV-III if band p24 or gp41 is present alone or in
combination with other bands.
* Notification of donors. If the repeat ELISA test is positive, or
if other tests are positive, it is the collection facility’s
responsibility to insure that the donor is notified. the donor should
be informed by an individual especially aware of the sensitivities
Currently, the proportion of seropositive donors who have been
infected with HTLV-III is unknown. Therefore it is important to
emphasize to the donor that the positive result is a preliminary finding
that may not represent a true infection. To determine the significance
of a positive test, the donor should be referred to a physician for
evaluation. The information should be gien in a way that insures the
confidentiality of the test result and the donor’s identity.
* Maintaining confidentiality. Physicians, laboratory and nursing
personnel, and others should recognize the importance of maintaining
confidentiality. Disclosure of positive test results for purposes other
than medical or public health could lead to serious consequences for the
individual. Screening procedures should be designed with safeguards to
protect donors against unauthorized disclosure.
Donors should receive a clear explanation of how information about
them will be handled. Facilities should consider contingency plans in
the event that disclosure is sought through the legal process. Donor
lists, where kept, should remain confidential. Whenever appropriate, as
an additional safeguard, deferral lists should be general, without
indication of the reason for inclusion.
* Medical evaluation. This might include ELISA testing of a
follow-up serum specimen and Western blot testing if the specimen is
positive. Persons who continue to show evidence of HTLV-III infection
should be questioned about possible exposure to the virus or possible
risk factors for AIDS in the individual or his/her sexual contacts.
They should be examined for signs of AIDS or related conditions,
such as lymphadenopathy, oral candidiasis, Kaposi’s sarcoma, and
unexplained weight loss. Additional lab studies might include tests for
other sexually transmitted diseases, tests of immune function, and,
where available, tests for the presence of the virus, such as viral
culture. Testing for antibodies to HTLV-III in the individual’s
sexual contacts may also be useful in establishing whether the test
results truly represent infection.
* Recommendations for the individual. An individual judged most
likely to have an HTLV-III infection should receive the following
information and advice:
1. The prognosis for an individual over the long term is not known.
However, data from studies conducted among homosexual men indicate that
most persons will remain infected.
2. Although asymptomatic, these individuals may transmit HTLV-III
to others. Regular medical evaluation and follow-up is advised,
especially for those who develop signs or symptoms suggestive of AIDS.
3. Refrain from donating blood, plasma, body organs, other tissue,
4. There is a risk of infecting others by sexual intercourse,
sharing of needles, and, possibly, exposure to others’ saliva
through oral-genital contact or intimate kissing. The efficacy of
condoms in preventing infection is unproved, but consistent use may
5. Toothbrushes, razors, or other implements that could become
contaminated with blood should not be shared.
6. Women with a seropositive test, or women whose sexual partner is
seropositive, are themselves at increased risk of acquiring AIDS. If
they become pregnant, their offspring are also at increased risk of
7. After accidents resulting in bleeding, contaminated surfaces
should be cleaned with household bleach diluted 1:10 in water.
8. Devices that have punctured the skin, such as hypodermic and
acupuncture needles, should be steam sterilized by autoclave before
reuse or safely discarded. Whenever possible, disposable products
should be used.
9. When seeking medical or dental care for intercurrent illness,
patients should report their antibody status to those responsible for
their care so that appropriate evaluations can be done and precautions
taken to prevent transmission to others.
10. Testing for HTLV-III antibody should be offered to persons who
may have been infected as a result of their contact with seropositvie
individuals (e.g., sexual partners, persons with whom needles have been
shared, infants born to seropositive mothers).
HHS said recommendations will be revised as more knowledge and
experience are gained with the new test.