Performance of a rapid, on-site human immunodeficiency virus antibody assay in a public health setting

Self-tests for influenza: an empirical ethics investigation

BACKGROUND

In this article we aim to assess the ethical desirability of self-test diagnostic kits for influenza, focusing in particular on the potential benefits and challenges posed by a new, mobile phone-based tool currently being developed by i-sense, an interdisciplinary research collaboration based (primarily) at University College London and funded by the Engineering and Physical Sciences Research Council.

METHODS

Our study adopts an empirical ethics approach, supplementing an initial review into the ethical considerations posed by such technologies with qualitative data from three focus groups.

RESULTS

Overall, we map a range of possible considerations both for and against the use of such technologies, synthesizing evidence from a range of secondary literature, as well as identifying several new considerations previously overlooked.

CONCLUSIONS

We argue that no single consideration marks these technologies as either entirely permissible or impermissible but rather tools which have the potential to incur certain costs and benefits, and that context is important in determining these. In the latter stages of the article, we explain how developers of such technologies might seek to mitigate such costs and reflect on the possible limitations of the empirical ethics method brought out during the study.

TRIAL REGISTRATION

Not applicable.

The proposed role of plasma NT pro-brain natriuretic peptide in assessing cardiac remodelling in hypertensive African subjects

AIM

Although plasma NT-proBNP differentiates hypertension (HT) with or without left ventricular hypertrophy (LVH) from hypertensive heart failure (HHF), most of the published data are based on studies in Western populations. Also, most previous studies did not consider left ventricular (LV) diastolic function and right ventricular (RV) function. We therefore examined the relation between NT-proBNP on LV and RV remodelling in an African hypertensive cohort.

METHODS

Subjects were subdivided into three groups after echocardiography: hypertensives without LVH (HT) (n = 83); hypertensives with LVH (HT + LVH) (n = 50); and those with hypertensive heart failure (HHF) (n = 77).

RESULTS

Subjects with HHF had significantly higher NT-proBNP levels compared to the HT + LVH group (p < 0.0002). NT-proBNP correlated positively with right atrial area, an indirect measure of RV function.

CONCLUSIONS

NT-proBNP is proposed as a useful biomarker in differentiating hypertension with or without LVH from hypertensive heart failure in black hypertensive subjects.

Diagnostic point-of-care tests in resource-limited settings

The aim of diagnostic point-of-care testing is to minimise the time to obtain a test result, thereby allowing clinicians and patients to make a quick clinical decision. Because point-of-care tests are used in resource-limited settings, the benefits need to outweigh the costs. To optimise point-of-care testing in resource-limited settings, diagnostic tests need rigorous assessments focused on relevant clinical outcomes and operational costs, which differ from assessments of conventional diagnostic tests. We reviewed published studies on point-of-care testing in resource-limited settings, and found no clearly defined metric for the clinical usefulness of point-of-care testing. Therefore, we propose a framework for the assessment of point-of-care tests, and suggest and define the term test efficacy to describe the ability of a diagnostic test to support a clinical decision within its operational context. We also propose revised criteria for an ideal diagnostic point-of-care test in resource-limited settings. Through systematic assessments, comparisons between centralised testing and novel point-of-care technologies can be more formalised, and health officials can better establish which point-of-care technologies represent valuable additions to their clinical programmes.

Assessment of the heat stability of seven rapid HIV assays

Human Immunodeficiency Virus Rapid Diagnostic Tests (HIV RDTs) are robust, quick to perform, effective diagnostic tools. The stability of seven commonly used RDTs for detecting antibody to HIV was assessed during exposure to temperatures above 30°C, the usual maximum recommended by manufacturers. The aim of the study was to determine if HIV RDTs retain their testing outcomes after exposure to higher temperatures. At two testing sites, seven RDTs were exposed to a short heat shock (60°C for 72 hours) as might occur during transport. RDTs were exposed to ambient (22 or 30°C), warm (35 or 37°C) or hot (45°C) temperatures for up to 90 days. Testing was performed at five intervals on a panel of seven positive and three negative plasma samples. Results showed no changes consistent with altered testing outcomes over time and/or temperature when test indicators were compared with the control indicators. Only one HIV RDT achieved 100% consensus with reference results at all four storage temperatures (median 97.5%, lowest 74% for RDT5 at 45°C). Testing outcomes in a limited sample panel showed six of seven HIV RDT kits were relatively robust despite exposure to higher than recommended temperatures.

Care and management of the infant of the HIV-1-infected mother

Mother-to-child transmission of the human immunodeficiency virus continues to be a major global health problem. The pediatric HIV-1 epidemic is fueled by HIV-1 infection in women of childbearing age with vertical transmission in utero or at the time of birth. In resource-rich countries, the birth of an infected child is a sentinel health event signaling a chain of missed opportunities and barriers to prevention. Because the fate and ultimate HIV-infection status of the baby is inextricably linked to the infection status of the mother and her general state of well-being, we provide in this review: 1) background and state-of-the-art management guidelines for optimum maternal care; 2) strategies to minimize the risk of vertical transmission of HIV; and 3) recommendations for managing infants born to HIV-infected women. These are discussed under four case scenarios that obstetric and pediatric providers frequently encounter in their practices.

Client satisfaction with rapid HIV testing: comparison between an urban sexually transmitted disease clinic and a community-based testing center

Rapid HIV testing allows same-day results, increasing the number of persons who learn their HIV status. Understanding how clients in different settings perceive rapid testing may increase acceptance of this technology. From June 1999 to August 2001 we interviewed 256 clients at a publicly funded urban sexually transmitted disease (STD) clinic and 1201 clients at a community- based HIV counseling, testing, and referral center (Los Angeles Gay and Lesbian Center; LAGLC) about their posttest satisfaction with rapid HIV testing. HIV prevalence was 3.9% at the STD clinic and 5.3% at the LAGLC. In multivariate analysis, adjusting for age, sexual orientation, race/ethnicity, history of STDs, self-perceived HIV risk, prior HIV test and HIV testing results, clients at the STD clinics (versus LAGLC) were more likely to find testing stressful (adjusted odds ratio [AOR]: 1.75, 95% confidence limits [CL]: 1.27, 2.42) and feel that they received their results too quickly (AOR: 2.05, 95% CL: 1.39, 3.03). Latinos (versus whites) were more likely to report that they received their results too quickly (AOR: 4.99, 95% CL: 3.48, 7.14) and that it would be better to wait a week for HIV test results (AOR: 2.48, 95% CL: 1.51, 4.09). Further research may elucidate the reasons why some groups prefer to wait for results, and enable policymakers to better design strategies to reach high-risk groups with rapid HIV testing.

Outcomes of Offering Rapid Point-of-Care HIV Testing in A Sexually Transmitted Disease Clinic

BACKGROUND

Delays in receipt of positive HIV test results and in entry into HIV care are common problems in clinics; in public venues, up to 33% of patients with negative results and 25% of those with positive results never learn their results.

METHODS

Patients aged 18 years or older at an urban sexually transmitted disease (STD) clinic were offered rapid HIV testing between October 1999 and August 2000. Specimens were tested using the rapid Single Use Diagnostic System for HIV-1 (SUDS; Abbott/Murex, Norcross, GA), and results were confirmed by conventional enzyme immunoassay and Western blot (WB) analysis. Trained health educators performed all HIV counseling, phlebotomy, and rapid testing.

RESULTS

Of 1977 eligible patients, 1581 (80%) agreed to HIV testing; of these, 1372 (87%) accepted rapid testing and 1357 (99%) received same-visit results and posttest counseling. Thirty-seven (2.7%) were HIV-positive as confirmed by WB analysis. One of these HIV-positive participants died, but the remaining 36 went to their first clinic appointment.

CONCLUSION

Rapid HIV testing was acceptable and feasible in this STD clinic and facilitated entry of newly identified HIV-infected patients into health care.

Evaluation and treatment of the human immunodeficiency virus-1--exposed infant

In developed countries, care and treatment are available for pregnant women and infants that can decrease the rate of perinatal human immunodeficiency virus type 1 (HIV-1) infection to 2% or less. The pediatrician has a key role in prevention of mother-to-child transmission of HIV-1 by identifying HIV-exposed infants whose mothers' HIV infection was not diagnosed before delivery, prescribing antiretroviral prophylaxis for these infants to decrease the risk of acquiring HIV-1 infection, and promoting avoidance of HIV-1 transmission through human milk. In addition, the pediatrician can provide care for HIV-exposed infants by monitoring them for early determination of HIV-1 infection status and for possible short- and long-term toxicities of antiretroviral exposure, providing chemoprophylaxis for Pneumocystis pneumonia, and supporting families living with HIV-1 infection by providing counseling to parents or caregivers.

Evaluation and treatment of the human immunodeficiency virus-1-exposed infant

In developed countries, care and treatment are available for pregnant women and infants that can decrease the rate of perinatal human immunodeficiency virus type 1 (HIV-1) infection to 2% or less. The paediatrician has a key role in the prevention of mother-to-child transmission of HIV-1 by identifying HIV-exposed infants whose mothers' HIV infection was not diagnosed before delivery, prescribing antiretroviral prophylaxis for these infants to decrease the risk of acquiring HIV-1 infection, and promoting avoidance of HIV-1 transmission through human milk. In addition, the paediatrician can provide care for HIV-exposed infants by monitoring them for early determination of HIV-1 infection status and for possible short- and long-term toxicities of antiretroviral exposure, providing chemoprophylaxis for Pneumocystis pneumonia, and supporting families living with HIV-1 infection by providing counselling to parents or caregivers.

Understanding the patient's perspective on rapid and routine HIV testing in an inner-city urgent care center

The purpose of this study was to explore patient perspectives of rapid and routine HIV-testing in an urgent care center at an urban public hospital. We conducted structured focus groups during a clinical trial comparing routinely offered rapid HIV-testing, routinely offered enzyme immunoassay (EIA) testing, and conventional EIA testing. Participants of the six focus groups were 89% African American, 60% uninsured, and had a low educational status. Four independent coders analyzed the data using iterative content analysis. Rapid testing was preferred to EIA testing because it reduced the need for a return visit and stress of waiting for test results, though there were concerns about accuracy. Participants supported routinely offering testing, but there were concerns about privacy and cost. Fear and stigma were common reasons for refusing testing and not returning for results. Distrust and misconceptions about HIV, particularly regarding the importance of testing, were very common.

Alternative HIV testing methods among populations at high risk for HIV infection

OBJECTIVE

The purpose of this study was to determine the levels of awareness and use of alternative HIV tests (home collection kit, oral mucosal transudate collection kit, and rapid tests) among people at high risk for HIV infection.

METHODS

Data were collected as part of an anonymous, cross-sectional interview study--the HIV Testing Survey (HITS)--conducted in seven states from September 2000 to February 2001. Three high-risk populations were recruited: men who have sex with men, injection drug users, and high-risk heterosexuals. Respondents were asked about their awareness and use of alternative HIV tests.

RESULTS

The overall awareness and use of the alternative tests was limited: 54% of respondents were aware of the home collection kit, 42% were aware of the oral mucosal transudate collection kit test, and 13% were aware of rapid tests. Among those aware of alternative tests, self-reported use of the tests was also low. The most common reasons given for not using alternative HIV tests were: preference for the standard test; concern that the results could be less accurate; and that alternative tests were not offered.

CONCLUSIONS

The low levels of awareness and use of alternative HIV tests suggest that the potential for promoting testing among individuals at high risk for HIV by encouraging use of alternative HIV tests has not been fully realized. Alternative tests should be made more broadly available and should be accompanied by education about these tests for physicians and people at risk. Educational efforts should be evaluated to determine if promoting alternative HIV tests increases the numbers of people at risk for HIV who are tested.

Cost comparison of three HIV counseling and testing technologies

BACKGROUND

In the United States, more than 2 million human immunodeficiency virus (HIV) antibody tests are performed annually at publicly funded HIV counseling and testing (CT) clinics. Clients do not receive results from one third of these tests because of low return rates. New rapid-testing technologies may improve receipt of results, but no study has systematically analyzed the costs of these newer technologies compared with the standard protocol.

OBJECTIVE

To estimate and compare the economic costs associated with three HIV CT protocols: the standard protocol and the one-step and two-step rapid protocols.

METHODS

A cost analysis model was developed in 2002 to calculate the intervention costs for HIV CT services with the standard CT protocol and the one-step and two-step rapid-test protocols for a hypothetical client in a publicly funded HIV clinic. Sensitivity analyses were performed to ascertain the effects of uncertainty in the model parameters.

RESULTS

The one-step rapid protocol was generally the least expensive of the three protocols. The standard protocol cost less than the two-step protocol per HIV-positive client notified of his or her HIV status, but cost more per HIV-negative client. The sensitivity analysis indicated overlap in the cost estimates for HIV-negative clients, reflecting the generally similar costs of the three testing protocols. Taking into account HIV seroprevalence, the two-step rapid protocol would be less expensive than the standard protocol for most publicly funded testing programs in the United States.

CONCLUSIONS

Rapid test protocols offer economic advantages as well as convenience, compared to the standard testing protocol. The cost estimates presented here should prove helpful to HIV program managers and other public health decision makers who need information on these counseling and testing technologies.

Overcoming barriers to HIV testing: preferences for new strategies among clients of a needle exchange, a sexually transmitted disease clinic, and sex venues for men who have sex with men

OBJECTIVE

To determine strategies to overcome barriers to HIV testing among persons at risk.

METHODS

We developed a survey that elicited testing motivators, barriers, and preferences for new strategies among 460 participants at a needle exchange, three sex venues for men who have sex with men, and a sexually transmitted disease clinic.

RESULTS

Barriers to testing included factors influenced by individual concern (fear and discrimination); by programs, policies, and laws (named reporting and inability to afford treatment); and by counseling and testing strategies (dislike of counseling, anxiety waiting for results, and venipuncture). The largest proportions of participants preferred rapid testing strategies, including clinic-based testing (27%) and home self-testing (20%); roughly equal proportions preferred oral fluid testing (18%), urine testing (17%), and standard blood testing (17%). One percent preferred home specimen collection. Participants who had never tested before were significantly more likely to prefer home self-testing compared with other strategies. Blacks were significantly more likely to prefer urine testing.

CONCLUSIONS

Strategies for improving acceptance of HIV counseling and testing include information about access to anonymous testing and early treatment. Expanding options for rapid testing, urine testing, and home self-testing; providing alternatives to venipuncture; making pretest counseling optional; and allowing telephone results disclosure may encourage more persons to learn their HIV status.

Performance characteristics of a rapid new immunochromatographic test for detection of antibodies to human immunodeficiency virus

A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doenças Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.

New methods for the detection of HIV

In the past few years, several strides have been made in the ability to detect the presence of HIV-1 and HIV-2. This article discusses recent advances in serologic testing, including routine ELISA and Western blot tests, rapid HIV tests, home collection kits, and HIV tests using nonserum samples. The clinical application of nucleic acid-based tests also is discussed. Finally, appropriate use of these tests in both acute HIV-1 infection and in infants is reviewed.

Low rate of false-positive results with use of a rapid HIV test

BACKGROUND

Occupational exposure to human immunodeficiency virus (HIV) is an important threat to healthcare workers. Centers for Disease Control and Prevention guidelines recommend prompt institution of prophylaxis. This requires (1) immediate prophylaxis after exposure, pending test results that may take more than 24 hours in many hospitals; or (2) performance of a rapid test. The Single Use Diagnostic System (SUDS) HIV-1 Test is used to screen rapidly for antibodies to HIV type 1 in plasma or serum, with a reported sensitivity of more than 99.9%. We used this test from January 1999 until September 2000, when it was withdrawn from the market following reports claiming a high rate of false-positive results.

METHODS

We reviewed the results of postexposure HIV testing during 21 months.

RESULTS

A total of 884 SUDS tests were performed on source patients after occupational exposures (883 negative results, 1 reactive result). The results of repeat SUDS testing on the reactive specimen were also reactive, but the results of enzyme immunoassay and Western blot testing were negative. A new specimen from the same patient showed a negative result on SUDS testing. This suggested a specificity of 99.9%. In the 4 months after SUDS testing was suspended, there was 1 false-positive result on enzyme immunoassay for 1 of 132 source patients (presumed specificity, 99.2%).

CONCLUSION

Use of the SUDS test facilitated rapid and accurate evaluation of source specimens, obviating unnecessary prophylaxis.

Comparison of murex single-use diagnostic system with traditional enzyme immunoassay for detection of exposure to human immunodeficiency virus

Because a retrospective study detected 13 negative Western blots out of 38 single-use diagnostic system (SUDS)-positive cases over a 1-year period, we performed a prospective study to compare the performance of the SUDS test with that of enzyme immunoassay (EIA). Of 888 SUDS-tested sera, 875 (98.4%) were both SUDS and EIA negative and 5 (0.6%) were SUDS, EIA, and Western blot positive. The rate of SUDS-positive samples decreased from 3.16/month in the retrospective study to 1.33/month in the prospective study. The immunoassays had sensitivities and specificities of 100 and 99.7 (SUDS) and 100 and 99.4% (traditional EIA), respectively. In laboratories with experienced personnel, the SUDS test performs as well as the EIA as a screen for infection with the human immunodeficiency virus.

Rapid hiv testing in urban outreach: a strategy for improving posttest counseling rates

In 1998, 48% of persons who had HIV testing at publicly funded sites in the United States failed to return for test results and posttest counseling. Opportunities for timely HIV therapy were lost; valuable resources were wasted. This study tested the hypothesis that rapid HIV testing enables a high percentage of high-risk outreach clients to learn their serostatus. We did on-site counseling and rapid HIV testing at community-based organizations (e.g., chemical dependency programs, homeless shelters) in North Minneapolis. The project tested 735 persons. All but one (99.9%) learned their HIV serostatus. African Americans made up 79% of subjects. Rapid testing has a role to play in HIV outreach. It is useful in populations who are at high risk of HIV infection, who currently are not accessing HIV testing, and who have high failure to return rates. Future developments in rapid testing technology will make this testing option more convenient and cost-effective.

Advantages of the rapid HIV-1 test in occupational accidents with potentially contaminated material among health workers

In occupational accidents involving health professionals handling potentially contaminated material, the decision to start or to continue prophylactic medication against infection by Human Immunodeficiency Virus (HIV) has been based on the ELISA test applied to a blood sample from the source patient. In order to rationalize the prophylactic use of antiretroviral agents, a rapid serologic diagnostic test of HIV infection was tested by the enzymatic immunoabsorption method (SUDS HIV 1+2, MUREX) and compared to conventional ELISA (Abbott HIV-1/ HIV-2 3rd Generation plus EIA). A total of 592 cases of occupational accidents were recorded at the University Hospital of Ribeirão Preto from July 1998 to April 1999. Of these, 109 were simultaneously evaluated by the rapid test and by ELISA HIV. The rapid test was positive in three cases and was confirmed by ELISA and in one the result was inconclusive and later found to be negative by ELISA. In the 106 accidents in which the rapid test was negative no prophylactic medication was instituted, with an estimated reduction in costs of US$ 2,889.35. In addition to this advantage, the good correlation of the rapid test with ELISA, the shorter duration of stress and the absence of exposure of the health worker to the adverse effects of antiretroviral agents suggest the adoption of this test in Programs of Attention to Accidents with Potentially Contaminated Material.

Characterization of microorganism identification in the United States in 1996

CONTEXT

The National Inventory of Clinical Laboratory Testing Services (NICLTS) was designed to give an unbiased estimate of all patient testing performed by laboratories registered under the Clinical Laboratory Improvement Amendments in 1996.

OBJECTIVE

Survey data were used to develop a profile of laboratory testing primarily intended to identify microorganisms or antibodies to these microorganisms.

DESIGN

Estimates of the extent of microorganism identification were derived from the NICLTS database by identifying associated tests and methods. The volumes for tests performed at locations that primarily prepared blood components for distribution were excluded. Organisms of public health importance were identified from the National Notifiable Disease list maintained by the Centers for Disease Control and Prevention.

PARTICIPANTS

Laboratories that were enrolled in the 1996 Online Certification Survey and Reporting System, maintained by the US Health Care Finance Administration, and that performed laboratory testing in 1996.

OUTCOME MEASURE

Estimated volumes and associated confidence limits by test, method, specimen type, public health importance, and testing location.

RESULTS

Excluding testing of the blood supply, 315 million tests (95% confidence limits, 280-354 million tests) were performed in the United States for microorganism identification. Those tests for which public health consensus requires national reporting represented 38% of this total. Although hospitals performed 46% of all microorganism identification, they only performed 33% of the testing for microorganisms of public health importance. Independent and specialty laboratories performed 38% of all testing but 65% of the testing for microorganisms of public health importance. Direct methods (methods not involving culture) were used in 77% of the tests for microorganisms of public health importance and in 42% of all identification tests.

CONCLUSIONS

The distribution of microorganism identification testing found using NICLTS data is consistent with plans to modernize the public health surveillance system in the United States.

Evaluation of United States-licensed human immunodeficiency virus immunoassays for detection of group M viral variants

Six Food and Drug Administration (FDA)-licensed human immunodeficiency virus type 1 (HIV-1) and HIV-1/2 immunoassays, including five enzyme immunoassays and one rapid test, were challenged with up to 250 serum samples collected from various global sites. The serum samples were from individuals known to be infected with variants of HIV-1 including group M subtypes A, B, B', C, D, E, F, and G and group O. All immunoassays detected the vast majority of samples tested. Three samples produced low signal over cutoff values in one or more tests: a clade B sample, an untypeable sample with a low antibody titer, and a group O sample. It is concluded that HIV-1 immunoassays used in the United States are capable of detecting most HIV-1 group M variants.

Laboratory testing for infection with the human immunodeficiency virus: established and novel approaches

The enzyme-linked immunosorbent assay (ELISA) and the Western blot are the primary tests for the diagnosis and confirmation of human immunodeficiency virus (HIV) infection. The ELISA, an inexpensive screening test for antibodies to HIV-1, is both sensitive and specific. The HIV-1 Western blot is a reliable confirmatory test following a repeatedly reactive ELISA. False-positive HIV-1 results with this sequence of tests are extremely rare but can occur, and test results that are inconsistent with clinical or other laboratory information should be questioned, repeated, or supplemented. The US Food and Drug Administration has also approved rapid and more accessible testing methods. Oral mucosal transudate and urine testing are noninvasive testing methods; rapid and home sample collection kits offer easier access to testing.

Diagnosis of human immunodeficiency virus type 1 infection with different subtypes using rapid tests

We evaluated six rapid tests for their sensitivity and specificity in diagnosing human immunodeficiency virus type 1 (HIV-1) infection using 241 specimens (172 HIV-1 positive, 69 HIV-1 negative) representing different HIV-1 subtypes (A [n = 40], B [n = 47], C [n = 28], E [n = 42], and F [n = 7]). HIVCHEK, Multispot, RTD and SeroStrip were 100% sensitive and specific. Capillus failed to identify two of eight subtype C specimens (overall sensitivity of 98. 85%), while the SUDS test (the only test approved by the Food and Drug Administration) gave false-positive results for 5 of 69 seronegative specimens (specificity of 93.24%). Our results suggest that although rapid tests perform well in general, it may be prudent to evaluate a rapid test for sensitivity and specificity in a local population prior to its widespread use.

Field evaluation of the Determine rapid human immunodeficiency virus diagnostic test in Honduras and the Dominican Republic

Rapid detection of human immunodeficiency virus (HIV) infection can result in improved patient care and/or faster implementation of public health preventive measures. A new rapid test, Determine (Abbott, Abbott Park, Ill.), detects HIV type 1 (HIV-1) and HIV-2 antibodies within 15 min by using 50 microl of serum or plasma. No specialized equipment or ancillary supplies are required, and results are read visually. A positive result is noted by the appearance of a red line. An operational control (red line) indicates proper test performance. We evaluated the Determine rapid HIV detection test with a group of well-characterized serum samples (CD4 counts and viral loads were known) and serum samples from HIV-positive individuals at field sites in Honduras and the Dominican Republic. In the field evaluations, the results obtained by the Determine assay were compared to those obtained by local in-country HIV screening procedures. We evaluated serum from 100 HIV-positive patients and 66 HIV-negative patients. All samples gave the expected results. In a companion study, 42 HIV-positive samples from a Miami, Fla., serum bank were tested by the Determine assay. The samples had been characterized in terms of CD4 counts and viral loads. Fifteen patients had CD4 counts <200 cells/mm(3), while 27 patients had CD4 counts >200 cells/mm(3). Viral loads ranged from 630 to 873,746 log(10) copies/ml. All samples from the Miami serum bank were positive by the Determine test. Combined results from the multicenter studies indicated that the correct results were obtained by the Determine assay for 100% (142 of 142) of the HIV-positive serum samples and 100% (66 of 66) of the HIV-negative serum samples. The Determine test was simple to perform and the results were easy to interpret. The Determine test provides a valuable new method for the rapid identification of HIV-positive individuals, especially in developing countries with limited laboratory infrastructures.

Major threats to childbirth in developing countries

Biological, psychological or social elements may constitute a threat to childbirth. In developing countries, major threats to childbirth mainly caused by restricted health service budgets may be overcome by the introduction of appropriate screening tests, implementation of evidence-based medicine protocols, and a primary health-care approach to maternity services.

Optimizing the delivery of HIV counseling and testing services: the Uganda experience using rapid HIV antibody test algorithms

The AIDS Information Center (AIC) was established in Kampala, Uganda in 1990 in response to increasing interest by members of the general public who wished to know their HIV serostatus. By 1996, >300,000 clients had been seen. HIV serologic testing was performed at a central laboratory and results reported back to AIC after 2 weeks. Approximately 25% of clients failed to learn their HIV serostatus as a result of failure to return or late arrival of results. To address these issues, AIC carried out an evaluation of 3 rapid HIV assays, Sero-Strip, SeroCard, and Capillus, against a standard criterion to identify a testing algorithm that could be used as an on-site confirmatory testing strategy. The study was carried out over a period of 5 working days and 325 clients were seen. An algorithm was identified, which gave no indeterminate results with unambiguously positive or negative specimens, which was 100% sensitive and specific, and which could be integrated with minimal disruption into existing counseling procedures. All clients left AIC knowing their HIV serostatus and having spent <2 hours at the Center. The results of this evaluation demonstrate that "same-day" results can be provided in counseling and testing settings without compromising the quality of counseling or the accuracy of HIV testing.

On-site, rapid HIV testing with same-day results and counseling

BACKGROUND

New rapid HIV antibody tests have allowed provision of results and result-specific counseling on the day on initial visit, and have the potential to increase the efficiency of HIV counseling and testing.

METHODS

To evaluate the use of rapid testing with same-day results in public clinics, the Single Use Diagnostic System HIV-1 rapid assay was used for a 3-month period at an anonymous testing clinic and a sexually transmitted disease (STD) clinic in Dallas, Texas. Non-reactive rapid test results were reported as HIV-negative. Reactive results were reported as 'preliminary positive'. These procedures were compared with standard testing during a baseline period, with respect to number of clients receiving results and post-test counseling, client satisfaction, counselor acceptance, cost and effectiveness at reducing HIV risk.

RESULTS

Rapid testing resulted in an increase in the number of persons learning their serostatus: a 4% increase for uninfected and a 16% increase for infected clients at the Anonymous Testing Clinic; a 210% increase for uninfected patients and a 23% increase for infected patients at the STD clinic. Rapid testing resulted in a cost saving of US$ 11 per test in both the anonymous and STD clinics. Of those previously tested, 88% responded that they preferred the rapid test. In the year following initial HIV test, clients tested with rapid and standard procedures were equally likely to return to the clinic with a new STD (odds ratio, 0.97; 95% confidence interval, 0.7-1.4).

CONCLUSIONS

Rapid, on-site HIV testing was feasible, preferred by clients, and, resulted in significant improvement in the number of persons learning their serostatus, without increasing the costs or decreasing the effectiveness of counseling and testing.