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A line from the song 'Politics and Poker,' from the Broadway musical Fiorello, goes: 'Neither game's for children, either game is rough. Decisions, decisions, like who to pick, how to bet, how to play, how to call a bluff.' Events in recent months, leading up to and following the release of CCD's recommendations for preventing transmission of HIV to patients by health care workers, can be characterized as a nation playing both games in trying to deal with undefinable or unexplainable risks of AIDS transmission. The nation seems split between those who favor politically astute (though not necessarily logically or ethically sound) solutions, and those who believe that HIV-infected practitioners must make decisions on testing, disclosure, and changes in practice based on a rational assessment of each individual case--factoring in the odds of viral transmission, the chance of losing a career, the interpretation of risk, adherence to stringent infection control technique, timing, patient confidence, and peer support. Ether one is a gamble. This special issue of Hospital Ethics takes a look at the politics and poker of AIDS testing and disclosure, with special attention to the kinds of advice being offered to hospitals as they develop policies on infected health care workers.

With heightened awareness that healthcare professionals may be a potential source of infection for the human immunodeficiency virus, calls for serial, mandatory testing and reporting are increasing. Fear and hysteria are particularly noticeable in rural settings, which are only now experiencing marked increases in the incidence of AIDS cases. While arguments for and against the merits of serial mandatory testing programs can be constructed, this paper presents support to oppose mandatory testing. Evidence for this stance is drawn from several sources, including epidemiologic, economic, and clinical research; as well as medical ethics literature.

Participation in external quality assessment (EQA) has been mandatory in France as from 1978. The Ministry of Health has responsibility for maintenance of a list of laboratories and contracts EQA schemes to be organised and supervised by scientific groups. Serological markers for viral hepatitis B and anti-HIV were included in surveys, four times per annum, as from 1985. The number of laboratories participating increased from 178 for anti-HIV and 499 for viral hepatitis markers in 1985 to 3421 for anti-HIV and 2384 for viral hepatitis markers at the present time. The percentage of correct results varies depending on the method and specimen from 98% to 99% for anti-HIV and from 95% to 97% for HBsAg; the false negative rate has been as high as 14% for anti-HBs.

The purpose of this study is to demonstrate the usefulness of meta-analysis and regression analysis in evaluating technologies by applying these techniques to an evaluation of the enzyme immunosorbent assay (EIA) human immunodeficiency virus (HIV) antibody test. This meta-analysis synthesizes 26 studies which report on sensitivity and specificity of the EIA HIV antibody test. Sensitivity and specificity values vary widely, ranging between 89-100% sensitivity and 67-100% specificity. To examine this variation, a regression model is tested that explains specificity as a function of the year the study was published, the population being sampled, and a quality rating. The model explains 29% of the total variation. The most significant determinant of specificity is the type of population sampled; studies with low prevalence samples have higher specificity. This study demonstrated that meta-analysis can be used to synthesize literature on technologies, and that regression analysis can be used to examine the sources of variation that meta-analysis uncovers. It also demonstrates the need for studies of test performance to use standardized research procedures and to fully report their methods and results.

Summarized are the results of an assessment of the major operational characteristics of 36 commercially available assays for detection of antibodies to human immunodeficiency virus type 1 (HIV-1) and/or type 2 (HIV-2). For this purpose, 20 enzyme-linked immunosorbent assays (ELISAs), 11 simple immunoassays with visual reading, four supplemental assays, and one discriminatory assay were assessed using a panel of 537 sera (65% of which were of African, 26% of European, and 9% of South American origin); the prevalence of HIV-1 was 39.1% and of HIV-2, 15.7%. The following operational parameters of the assays were investigated: ease of performance; suitability for use in small blood collection centres; sensitivity and specificity; positive predictive values at different prevalences; inter-reader variability for simple assays whose results were read visually; the proportion of indeterminate results; and, for some of the ELISA assays, delta-values, as quantitative measures of sensitivity and specificity. The results will be of use to health policy decision-makers, managers of national AIDS prevention and control programmes, directors of blood banks, and laboratory specialists in the selection of appropriate HIV antibody assays.

Long used as a public health tool for controlling sexually transmitted diseases, partner notification has been underutilized against HIV infection. Why? Issues of confidentiality, cost-effectiveness, and clinical benefit are involved. The validity of these concerns is addressed in a review of recent experience in Colorado and elsewhere.

In HIV tests, the sensitivity is important, but even more so is the specificity, i.e., the reliability of positive tests results. A third parameter, the positive predictive value, is connected with these test characteristics; but even more it depends to a high degree on the prevalence of the infection. To solve these general problems, highly purified virus antigens as well as step testing are used in HIV diagnosis. Initially, screenings test (ELISA, IFA, various so-called quick tests) are used to filter out those suspected of being infected from the mass of non-infected persons. For this population with an increased HIV prevalence, confirmation tests are performed. With the indirect immunofluorescence assay, it is possible to distinguish antiviral from anticellular antibody reactions. With the so-called immunoblot, the immune response against individual virus proteins can be determined. The sensitivity of HIV tests is approximately 99-100%. As for the specificity, only 1 false positive result per 50,000-100,000 tests is expected. AIDS infections before seroconversion can be diagnosed only by detecting the virus or compounds of it. This is hardly possible with virus Antigen-ELISA and virus cultivation. On principle, nucleic acid hybridisation after DNA multiplication by polymerase chain reaction would be suitable. However, there are still some technical problems and questions of interpretation of results with this method. It is also very complicated and thus out of the question for routine examination.

Since december 1st 1988, the Retrovirus study Group of the French Society of Blood Transfusion has initiated a systematic multicentric control of all anti-HIV screening EIA test kits lots used by each member of the group. For this purpose a special panel (GRV) has been designed and forwarded to each laboratory. From december 1st 1988 to august 8 1989, 6 HIV-1 kits have been in use (Diagnostics Pasteur Elavia 1; Diagnostics Pasteur Rapid'Elavia; Organon Vironostika; Abbott HIV recombinant; Du Pont env 9; Wellcome Wellcozyme). The GRV panel has been run 204 times on 102 different lots in 12 laboratories. Results after 9 months show that these 6 kits almost always properly recognize the 5 HIV 1 positive samples of the panel. However they differ in their ability to recognize HIV 2 positive samples. Variations in results are observed from lot to lot as well as between the first half of this period and the second.

The stability of two most important components of the EIA test system for diagnosis of HIV infection, an immunosorbent (HIV antigen adsorbed on polystyrene plates) and antispecies peroxidase conjugate, was studied. The possibility to prolong the shelf life of the test system for at least up to 6 months was demonstrated. At the same time, it is proposed to supplement the existing methods of production control with the conjugate thermostability test developed by the authors who believe that this will allow to exclude conjugates with insufficient stability from the test system kit.

In 1986, the Centers for Disease Control (CDC) implemented the Model Performance Evaluation Program (MPEP) to evaluate the performance of laboratories that test for antibody directed against human immunodeficiency virus type 1 (HIV-1). The impetus for developing this program came from the recognition of a need to assess the quality of existing and changing laboratory technology and to ensure that the quality of testing was sufficient to meet medical and public health needs. To develop the program, CDC chose HIV-1 antibody testing as the first specific application for assessing the quality of laboratory performance because (a) of the importance of accurate and reproducible test results for acquired immunodeficiency syndrome (AIDS) surveillance, prevention, and treatment programs; (b) HIV-1 testing technology is new to many laboratories; and (c) HIV-1 testing practices and applications continue to evolve. Unlike proficiency testing programs, the MPEP is not limited to assessing quality in the analytical step, alone. It will also assess quality in the preanalytical and postanalytical steps of the testing process, that is, from the time a test is requested until the clinician who ordered the test takes an action based on the test result. The participating laboratories furnish the information needed for the performance evaluation program by (a) completing questionnaires designed to describe HIV-1 testing laboratories and their testing practices, (b) analyzing specially prepared sample panels for HIV-1 antibody reactivity, and (c) reporting results to CDC.

The American Association of Blood Banks/College of American Pathologists Viral Marker Survey program added samples to evaluate participant performance with test systems for the detection of antibodies to human immunodeficiency virus type 1 in 1985. On the 80 challenges sent through April 1989, the major problem observed with enzyme immunoassay testing was unexpected reactivity on samples that did not contain anti-human immunodeficiency virus type 1. One manufacturer's testing system accounted for most of the specificity problems. The sensitivity of the enzyme immunoassay for anti-human immunodeficiency virus type 1 is close to 99%, based on the multiple reactive samples used on the 16 panels. Between 1985 and 1989, there was a 14-fold increase in participants reporting Western blot results. The introduction of a licensed system for Western blots increased the number of samples that contained antibody to human immunodeficiency virus type 1 interpreted as indeterminate. Answers to supplementary questions showed that the rate of repeatably reactive and confirmed positives on blood donors dropped to less than 0.1%.

The materials on the development of a reference panel of HIV-positive and negative blood sera required for quality control of diagnostic enzyme-immunoassay systems are summarized. Ninety sera (50 HIV-antibody positive and 40 negative) were examined in 2 test systems of national and 3 test systems of foreign companies as well as by immune blotting and immunofluorescence tests. Each serum was characterized by optic density values and antibody titer (for positive sera). The conditions of storage and transportation of serum panels as well as those for control tests were determined. The license and instructions for use for the serum panel have been approved. The serum panel is used in 9 institutions engaged in working out and manufacture of diagnostic test systems.

Since licensure of the first human immunodeficiency virus type 1 screening assay in March 1985, there has been a need for well-characterized human immunodeficiency virus type 1 reference sera. These sera would be used in an effort to ensure uniformity of human immunodeficiency virus type 1 test results worldwide. Three major organizations--the World Health Organization, the Pan American Health Organization, and the National Committee for Clinical Laboratory Standards working with the College of American Pathologists--have ongoing programs aimed at the preparation of these reference sera. All three organizations are preparing both negative and human immunodeficiency virus type 1 seropositive sera. In addition, one organization is preparing early sero-converter and late acquired immunodeficiency syndrome samples. The status of these efforts and the serologic characteristics of the sera were reviewed.

The results of HIV testing must protect public health while preserving individual rights against unnecessary intrusions. To determine whether actual risks justify mandatory testing and reporting, the best possible objective medical information must be considered. Legislators and courts must not cave in to public sentiment and fears. Courts must scrutinize HIV testing legislation carefully to ensure that the legislative history is accurate and the primary goal is concern for public health, not for discriminating or creating scapegoats.

The purpose of this article is to describe the legal approach, and in particular, the specific statutory vehicle adopted by the U.S. with respect to unlinked anonymous screening, and to offer the U.S. approach as a possible model for those countries presently considering the implementation of unlinked HIV screening programs. Clear legal authorization for unlinked anonymous HIV testing is provided for by statute or regulation in the U.S. Federal regulations and various state laws specifically permit unlinked anonymous testing. Under these regulations and statutes, informed consent of a test subject is not required so long as testing is done for research purposes and the test results are not individually traceable to particular subjects.

In response to the public outcry for mandatory testing for AIDS, this Article explores the major issues concerning the identification of persons with AIDS in society. The Article first studies testing procedures and the purposes behind them to determine if a call for mandatory testing of the general populace would better achieve society's objectives for identifying individuals with AIDS. Concluding that testing should not be required of the population as a whole, the Article then explores whether testing should be required of certain subpopulations which society perceives as likely to have or to spread the disease. In this context, too, the Article concludes that mandatory testing would be unwarranted, and that funds proposed for mandatory testing would be put to better use in education and universal precautions to prevent the further spread of AIDS.

Here's the evolving law on such matters as transfusion-transmitted AIDS, false positives and negatives, disclosure of test results, protection of the health care staff, and employees who refuse to work with AIDS patients.