Anticipating that blood tests for detecting AIDS virus antibodieswill be available this month, the Government has announced newrecommendations for screening donated blood and plasma. The Public Health Service’s proposed approach covers bloodtesting procedures, the appropriateness of repeat tests, and steps forinforming persons whose test results are positive. The agency counselsphysicians on what medical measures to use and advice to give forpatients who test positive. PHS’s suggestions include ways toprevent further spread of the disease. It also stresses the need tomaintain confidentiality. “These Public Health Service recommendations are an importantstep forward in meeting our responsibility to the American people,”said Health and Human Services Secretary Margaret Heckler during arecent press conference. Federal health officials estimate that lessthan 1 per cent of blood donors will have positive, confirmed resultsshowing the presence of antibodies to HTLV-III, the virus believed tocause AIDS. Heckler said it is particularly important to emphasize theuncertainty of the link between positive test results and thedisease’s course.
“All our scientific evidence to dateindicates that although many people may have been exposed to the AIDSvirus, 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, and106 were transfusion-related. Last April, PHS researchers isolated HTLV-III, developed aprototype antibody detection kit, and licensed five firms (AbbottLaboratories, Du Pont/Biotech, Electro-Nucleonics, Litton Bionetics, andTravenol-Genentech) to refine and mass-produce the test kits. By allaccounts, the companies’ efforts have proceeded smoothly, stickingto hoped-for deadlines and encountering no scientifc surprises.
A recent Journal of the American Medical Association report byresearchers representing several institutions found that the test, intrials, had spotted HTLV-III antibodies in 82 per cent of 88 patientsknown to have AIDS. For another 16 per cent, results were borderline,while 2 per cent of AIDS patients did not have antibodies. Meanwhile, Uper cent of 297 volunteer blood donors had the antibody, 6 per cent wereborderline, and 93 per cent negative. The report concluded that the test is “highly specific andsensitive for AIDS.
” Still, while the Science might be encouraging to some, others findthe imperfections in the test unsettling. At an American BloodCommission conference shortly after Secretary Heckler’s publicpraise for the near-ready kit, opinion appeared split over the PHSrecommendations for use and counseling. Moreover, some within the gay community have urged a boycott of thetest. 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 bedangerously unreliable.
” Because most AIDS victims are gay, he claimed, the test will beused “as a marker for homosexuality. There are at present no legalprotections guarding test results from health insurers, employers, oreven the Government itself.” He added: “Nobody, least of all a gay man, should allow thistest to be done on his or her blood except as part of a research programoffering maximum protection of results, with the highestconfidentiality.” Noting also that no member of at-risk groups forAIDS should donate blood, McFarlane warned, “Until other tests areintroduced, especially tests that confirm the presence of the virusitself, the antibody test alone can only serve to darken forever thelife of anyone who tests positive.
” At this writing, HHS expected to be clearing “more thanone” of the test kits for commercial distribution by the end ofFebruary. The department also planned to mail to the nation’s bloodbanks a set of instructions elaborating on the PHS recommendations. Aseparate special letter was to go out to all practicing physicians inthe United States with suggestions on care and follow-up for those whomay test positive. The following are PHS-recommended procedures for the antibodytest’s administration: * Initial screening. Persons accepted as donors should be informedthat their blood or plasma will be tested for HTLV-III antibody.Persons not wishing to have their blood tested must refrain fromdonating. Donors should be told they will be notified if their test ispositive and that they may be placed on the collection agency’sdonor deferral list, as is currently done for other infectious diseases.They should further be informed of other deferral lists to whichpositive donors’ names may be added.
All blood or plasma should be tested for HTLV-III antibody by theenzyme-linked immunosorbent assay (ELISA) test. Any blood or plasamfound positive on initial testing must not be transfused or manufacturedinto other products capable of transmitting infectious agents. WhenELISA is used to screen populations in whom the prevalence of HTLV-IIIinfections is low, the proportion of positive results that are falselypositive will be high. Therefore, the ELISA should be repeated on allseropositive specimens before the donor is notified.
If the repeatELISA test is negative, the specimen should be tested by another test. * Other testing. Other tests have included immunofluorescence andradioimmunoprecipitation assays. But the most extensive experience hasbeen with the Western blot technique, in which antibodies can bedetected to HTLV-III proteins of specific molecular weights. Based onavailable data, the Western blot should be considered positive forantibody to HTLV-III if band p24 or gp41 is present alone or incombination with other bands.
* Notification of donors. If the repeat ELISA test is positive, orif other tests are positive, it is the collection facility’sresponsibility to insure that the donor is notified. the donor shouldbe informed by an individual especially aware of the sensitivitiesinvolved. Currently, the proportion of seropositive donors who have beeninfected with HTLV-III is unknown.
Therefore it is important toemphasize to the donor that the positive result is a preliminary findingthat may not represent a true infection. To determine the significanceof a positive test, the donor should be referred to a physician forevaluation. The information should be gien in a way that insures theconfidentiality of the test result and the donor’s identity. * Maintaining confidentiality. Physicians, laboratory and nursingpersonnel, and others should recognize the importance of maintainingconfidentiality. Disclosure of positive test results for purposes otherthan medical or public health could lead to serious consequences for theindividual.
Screening procedures should be designed with safeguards toprotect donors against unauthorized disclosure. Donors should receive a clear explanation of how information aboutthem will be handled. Facilities should consider contingency plans inthe event that disclosure is sought through the legal process.
Donorlists, where kept, should remain confidential. Whenever appropriate, asan additional safeguard, deferral lists should be general, withoutindication of the reason for inclusion. * Medical evaluation.
This might include ELISA testing of afollow-up serum specimen and Western blot testing if the specimen ispositive. Persons who continue to show evidence of HTLV-III infectionshould be questioned about possible exposure to the virus or possiblerisk 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, andunexplained weight loss. Additional lab studies might include tests forother sexually transmitted diseases, tests of immune function, and,where available, tests for the presence of the virus, such as viralculture. Testing for antibodies to HTLV-III in the individual’ssexual contacts may also be useful in establishing whether the testresults truly represent infection. * Recommendations for the individual. An individual judged mostlikely to have an HTLV-III infection should receive the followinginformation and advice: 1.
The prognosis for an individual over the long term is not known.However, data from studies conducted among homosexual men indicate thatmost persons will remain infected. 2. Although asymptomatic, these individuals may transmit HTLV-IIIto 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,or sperm. 4. There is a risk of infecting others by sexual intercourse,sharing of needles, and, possibly, exposure to others’ salivathrough oral-genital contact or intimate kissing. The efficacy ofcondoms in preventing infection is unproved, but consistent use mayreduce transmission. 5. Toothbrushes, razors, or other implements that could becomecontaminated with blood should not be shared. 6.
Women with a seropositive test, or women whose sexual partner isseropositive, are themselves at increased risk of acquiring AIDS. Ifthey become pregnant, their offspring are also at increased risk ofacquiring AIDS. 7. After accidents resulting in bleeding, contaminated surfacesshould be cleaned with household bleach diluted 1:10 in water.
8. Devices that have punctured the skin, such as hypodermic andacupuncture needles, should be steam sterilized by autoclave beforereuse or safely discarded. Whenever possible, disposable productsshould be used. 9. When seeking medical or dental care for intercurrent illness,patients should report their antibody status to those responsible fortheir care so that appropriate evaluations can be done and precautionstaken to prevent transmission to others.
10. Testing for HTLV-III antibody should be offered to persons whomay have been infected as a result of their contact with seropositvieindividuals (e.g.
, sexual partners, persons with whom needles have beenshared, infants born to seropositive mothers). HHS said recommendations will be revised as more knowledge andexperience are gained with the new test.