Human Immunodeficiency Virus Testing Algorithm Research Articles

391. Modified Human Immunodeficiency Virus Testing Algorithm in Rural Missouri (MOdified HIV testing algorithm)

Abstract Background Universal screening for human immunodeficiency virus (HIV) is essential for timely and accurate diagnosis of HIV. The Centers for Disease Control and Prevention (CDC) recommends an algorithm that begins with HIV-1/HIV-2 Ag/Ab combination assay (HIV screening), which if reactive, is followed by HIV-1/HIV-2 antibody differentiation assay. If the differentiation assay is negative (discordant results), nucleic acid test for HIV RNA should follow. The University of Missouri Health Care (MUHC) sends the antibody differentiation assay to a reference laboratory, leading to delays in turn-around-time (TAT). As MUHC performs HIV-1 RNA testing in-house, we modified our own HIV screening algorithm to reflex HIV-1 RNA testing following a reactive HIV screening, with the goal of reducing TAT. Human Immunodeficiency Virus Screening Algorithm The above is the screening algorithm for human immunodeficiency virus (HIV) recommended by the Centers for Disease Control and Prevention utilized during period 1. Methods Data from positive HIV screening tests was collected from two periods: period 1 (1/1/2021-12/29-2022), in which MUHC followed the screening algorithm recommended by the CDC (Figure 1); and period 2 (12/30/2022-12/31/2023) in which MUHC followed the Modified HIV testing algorithm (Figure 2). In both algorithms, if the test that follows a reactive HIV screening is positive, the patient is determined to have confirmed HIV infection. If negative, additional testing is performed to determine if reactive HIV screening was false positive or true positive. The TAT were collected and the differences in TAT between the two periods were analyzed using a two-sample t-test. MOdified Human Immunodeficiency Virus Screening Algorithm Above is the modified HIV screening algorithm utilized during period 2 in which the HIV-1 RNA is the first test following the reactive HIV screening test. Results 47 positive HIV screenings tests were analyzed in period 1 and 66 in period 2. The mean TAT between a reactive HIV screening and the differentiation assay result in period 1 was 3.6 days, whereas the TAT between a reactive HIV screening and the HIV RNA result in period 2 was 2.3 days (p 0.04). A higher percentage of tests were resulted in 1-3 days in period 2 compared to period 1 (77.2% vs 68.1%). Turn Around Time Comparison On the left is the data from first period where University of Missouri Healthcare utilized the CDC recommended algorithm. The data on the right is from the second period utilizing the modified algorithm. Conclusion At our institution, after modification of the HIV testing algorithm to reflex RNA testing after a reactive HIV screening, patients received a faster confirmation of HIV diagnosis compared to CDC’s algorithm. This intervention could expedite linkage to care and initiation of antiretroviral therapy, especially at small and midsize institutions that often do not have the differentiation assay in-house. Disclosures Dima Dandachi, MD, MPH, Gilead Sciences: Grant/Research Support|ViiV Healthcare: Grant/Research Support|ViiV Healthcare: Honoraria

DETECTION OF NEW HIV CASES UNDER EPIDEMIC CONTROL - WHEN IS IT THE RIGHT TIME TO REVIEW HIV TESTING ALGORITHMS FOR COUNTRIES NEARING THE 95-95-95 MILESTONES? CASE STUDY -BOTSWANA.

Accurate diagnosis of human immunodeficiency virus (HIV) infection is dependent on using established national HIV testing algorithm. The purpose of this study was to review published articles to identify, and apply lessons learned to determine factors affecting transition of HIV testing algorithm for countries that have attained HIV epidemic control. We systematically searched peer-reviewed articles from online scientific databases; PubMed and Google Scholar from January 2019 to March 2024, using defined search phrases to extract articles. The defined search terms targeted articles focusing on issues of attained epidemic control and transitioning of HIV testing algorithm. Descriptive analysis was used to develop themes to answer the research question. The findings show that countries should consider the following areas before changing their HIV testing algorithm: (i) evaluate the current national HIV testing algorithm to determine the Positive Predictive Value (PPV), which should be ≥ 99%, (ii) evaluate test kits bearing both CE and FDA certification and are WHO pre-qualified (iii) 4th generation Rapid Diagnostic Tests (RDTs) are less sensitive than laboratory-based 4th generation assays, (iv) pilot the proposed algorithm before country-wide roll-out, (v) country specific policies, and framework are required to guide transition, and (vi) a combination of 4th and 3rd generation RDTs can achieve desired PPV. Transitioning HIV testing algorithm for countries reaching HIV epidemic control is a multistep process which considers the PPV of the current algorithms, considers policies and framework to guide the process and, evaluates a combination of 4th and 3rd generation RDTs.

High Prevalence of Unconfirmed Positive HIV Polymerase Chain Reaction Test Results Among African Infants With HIV Exposure in the International Epidemiology Databases to Evaluate AIDS Consortium.

In a large, multiregional cohort of African infants with human immunodeficiency virus (HIV) exposure, 44% of those with a positive HIV polymerase chain reaction test lacked a confirmatory positive test. Efforts are needed to ensure high-fidelity implementation of HIV testing algorithms so that all positive results are confirmed.

Declining Trend of HIV Seroprevalence in Pregnant Women: A Retrospective Observational Analysis of 12 Years’ Experience at a Tertiary Care Hospital in Central India

Introduction: Human Immunodeficiency Virus (HIV) infection among antenatal women has been reported throughout the country, with a relatively high prevalence in the state of Maharashtra. Data on HIV seroprevalence in antenatal women serve as an indirect indicator of the HIV epidemic's burden in the general population and aid in predicting the same in young children. Diagnostic and treatment services for HIV are concentrated in selected states and districts with high seroprevalence, making it necessary to accurately calculate the prevalence of HIV. Aim: To assess the effectiveness of Prevention of Parentto-Child Transmission (PPTCT) services and to study the effectiveness of the National Acquired Immunodeficiency Syndrome (AIDS) Control Programme (NACP) in the functioning of PPTCT services. Materials and Methods: A retrospective observational analysis of 12-year data, from January 2007 to December 2018, was conducted in the Department of Microbiology at the Government Medical College and Hospital, Nagpur, Maharashtra, representing Central India. Data collection took place from June 2019 to December 2019, and analysis occurred over the subsequent two months (January 2020 to February 2020). The total sample size was 101,865 patients. All pregnant women registered in the Antenatal Clinic (ANC) under the PPTCT Program were included in the present study, and Strategy III of the National HIV testing algorithm was followed. The women's ages, their partners' serostatus, and records of babies born to HIV seropositive mothers were obtained and analysed. The statistical analysis of the data was performed using Stata (version 10.4.2009, STATA Corp., Texas, USA) and Epi Info 7 (version 7.1.06, 2012, CDC, Atlanta, USA), employing the Chi-square test for linear trend (Extended Mantel-Haenszel). A p-value <0.05 was considered significant. Results: The seroprevalence of HIV infection among pregnant women was 1.04% in 2007, decreasing to 0.23% by 2017. In 2009, 88.9% of women were counselled, and 100% were tested for HIV, with pretest counselling steadily increasing to 100% by 2012. The trend in HIV testing, however, remained at 100% over the span of 10 years. Post-test counselling varied from 89.6% to 99.9%, whereas the trend of HIV testing among partners fluctuated from 50% to 94.44%. The overall HIV positivity among babies, after 18 months of follow-up, was 4.77%. Conclusion: The HIV seroprevalence among the pregnant population is steadily declining. More and more women are availing themselves of the facilities at Integrated Counselling and Testing Centre (ICTC). Intensive health education and the availability of diagnostic and therapeutic services across the country have reduced the burden of the HIV/AIDS problem in the country

HIV rapid test performance among health facilities enrolled in HIV rapid test quality improvement initiative (RTQII) in Ethiopia

BackgroundAs the Human Immunodeficiency Virus (HIV) rapid testing services expanded to reach the global target that 95% of people living with the virus will know their status by 2030, ensuring the quality of those services becomes critical. This study was conducted to assess the performance of HIV Rapid testing at sites in health facilities that were enrolled in the Rapid Test Quality Improvement Initiative (RTQII) in Ethiopia.MethodsCharacterized HIV proficiency testing (PT) panels of Dried Tube Specimen (DTS) were prepared, verified, and distributed to testing sites from August to December 2019. In addition on-site evaluation of HIV testing sites (HTSs) was conducted using a checklist to assess testing conditions. For proficiency testing, the study included 159 HIV testing sites (HTSs) in 41 Health facilities (HFs) in five administrative regions and two city administrations. The collected data was analyzed by SPSS version 20 and chi-square test was applied to identify the association between acceptable performance and contributing factors. Testing sites with 100% PT score as well as conducting the test with adherence to the National HIV Testing Algorithm were considered acceptable.ResultsThe overall acceptable performance (100% PT score with the correct algorithm followed) was found to be 62% while 12% scored 80% and 11% scored between 20 and 60%. The rest 15% were not considered as acceptable due to failure to adhere to the National HIV Testing Algorithm. Testing sites that participated in External Quality Assessment/Proficiency Testing schemes have shown better performance than those that did not participate with 70% and 56% performance respectively (p = 0.057).

Evaluation of the Nigeria national HIV rapid testing algorithm.

Human Immunodeficiency Virus (HIV) diagnosis remains the gateway to HIV care and treatment. However, due to changes in HIV prevalence and testing coverage across different geopolitical zones, it is crucial to evaluate the national HIV testing algorithm as false positivity due to low prevalence could be detrimental to both the client and the service delivery. Therefore, we evaluated the performance of the national HIV rapid testing algorithm using specimens collected from multiple HIV testing services (HTS) sites and compared the results from different HIV prevalence levels across the six geopolitical zones of Nigeria. The evaluation employed a dual approach, retrospective, and prospective. The retrospective evaluation focused on a desktop review of program data (n = 492,880) collated from patients attending routine HTS from six geopolitical zones of Nigeria between January 2017 and December 2019. The prospective component utilized samples (n = 2,895) collected from the field at the HTS and tested using the current national serial HIV rapid testing algorithm. These samples were transported to the National Reference Laboratory (NRL), Abuja, and were re-tested using the national HIV rapid testing algorithm and HIV-1/2 supplementary assays (Geenius to confirm positives and resolve discordance and multiplex assay). The retrospective component of the study revealed that the overall proportion of HIV positives, based on the selected areas, was 5.7% (28,319/492,880) within the study period, and the discordant rate between tests 1 and 2 was 1.1%. The prospective component of the study indicated no significant differences between the test performed at the field using the national HIV rapid testing algorithm and the re-testing performed at the NRL. The comparison between the test performed at the field using the national HIV rapid testing algorithm and Geenius HIV-1/2 supplementary assay showed an agreement rate of 95.2%, while that of the NRL was 99.3%. In addition, the comparison of the field results with HIV multiplex assay indicated a sensitivity of 96.6%, the specificity of 98.2%, PPV of 97.0%, and Kappa Statistic of 0.95, and that of the NRL with HIV multiplex assay was 99.2%, 99.4%, 99.0%, and 0.99, respectively. Results show that the Nigeria national serial HIV rapid testing algorithm performed very well across the target settings. However, the algorithm's performance in the field was lower than the performance outcomes under a controlled environment in the NRL. There is a need to target testers in the field for routine continuous quality improvement implementation, including refresher trainings as necessary.

Trends in HIV-2 Diagnoses and Use of the HIV-1/HIV-2 Differentiation Test - United States, 2010-2017.

Since 2014, the recommended laboratory testing algorithm for diagnosing human immunodeficiency virus (HIV) infection has included a supplemental HIV-1/HIV-2 differentiation test to confirm infection type on the basis of the presence of type-specific antibodies (1). Correctly identifying HIV-1 and HIV-2 infections is vital because their epidemiology and clinical management differ. To describe the percentage of diagnoses for which an HIV-1/HIV-2 differentiation test result was reported and to categorize HIV type based on laboratory test results, 2010-2017 data from CDC's National HIV Surveillance System (NHSS) were analyzed. During 2010-2017, a substantial increase in the number of HIV-1/HIV-2 differentiation test results were reported to NHSS, consistent with implementation of the HIV laboratory-based testing algorithm recommended in 2014. However, >99.9% of all HIV infections identified in the United States were categorized as HIV-1, and the number of HIV-2 diagnoses (mono-infection or dual-infection) remained extremely low (<0.03% of all HIV infections). In addition, the overall number of false positive HIV-2 test results produced by the HIV-1/HIV-2 differentiation increased. The diagnostic value of a confirmatory antibody differentiation test in a setting with sensitive and specific screening tests and few HIV-2 infections might be limited. Evaluation and consideration of other HIV tests approved by the Food and Drug Administration (FDA) that might increase efficiencies in the CDC and Association of Public Health Laboratories-recommended HIV testing algorithm are warranted.

Evaluation of antenatal rapid human immunodeficiency virus testing in rural South Africa.

South African guidelines recommend two rapid tests for diagnosing human immunodeficiency virus (HIV) using the serial HIV testing algorithm, but the accuracy and compliance to this algorithm is unknown in rural clinics. We evaluated the accuracy of HIV rapid testing and the time to receiving test results among pregnant women in rural KwaZulu-Natal (KZN). We observed the accuracy of rapid HIV testing algorithms for 208 consenting antenatal patients accessing voluntary HIV testing services in nine rural primary healthcare (PHC) clinics in KZN. A PHC-based HIV counsellor obtained finger-prick whole blood from each participant to perform rapid testing using the Advanced Quality™ One Step anti-HIV (1&2) and/or ABON™ HIV 1/2/O Tri-Line HIV test. A research nurse obtained venous blood for an enzyme-linked immunosorbent assay (ELISA) HIV test, which is the gold standard diagnostic test. We recorded the time of receipt of HIV test results for each test. Among 208 pregnant women with a mean age of 26 years, 72 women from nine rural PHC clinics were identified as HIV-positive by two rapid tests with an HIV-prevalence of 35% (95% Bayesian credibility intervals [BCI]: 28% - 41%). Of the 208 patients, 135 patients from six clinics were tested with the serial HIV testing algorithm. The estimated sensitivity and specificity for the 135 participants were 100% (95% confidence interval [CI]: 93% - 100%) and 99% (CI: 95% - 100%), respectively. The positive predictive value and negative predictive value were estimated at 98% (CI: 94% - 100%) and 95% (CI: 88% - 99%), respectively. All women received their HIV rapid test results within 20 min of testing. Test stock-out resulted in poor test availability at point-of-care, preventing performance of a second HIV test in three out of nine PHC clinics in rural KZN. Despite the poor compliance with national guidelines for HIV rapid testing services, HIV rapid test results provided to pregnant women in rural PHC clinics in KZN were generally accurate and timely. Test stock-out was shown to be one of the barriers to test availability in rural PHC clinics, resulting in poor compliance with guidelines. We recommend a compulsory confirmation HIV rapid test for all HIV-negative test results obtained from pregnant patients in rural and resource-limited settings.

Rapid Diagnostic Testing of Hospitalized Malawian Children Reveals Opportunities for Improved HIV Diagnosis and Treatment.

Recent World Health Organization (WHO) guidelines recommend antiretroviral therapy (ART) for all HIV-infected people; previously CD4+ T lymphocyte quantification (CD4 count) or clinical staging determined eligibility for children ≥ 5 years old in low- and middle-income countries. We examined positive predictive value (PPV) of a rapid diagnostic test (RDT) algorithm and ART eligibility for hospitalized children with newly diagnosed HIV infection. We enrolled 363 hospitalized Malawian children age 2 months to 16 years with two serial positive HIV RDT from 2013 to 2015. Children aged ≤ 18 months whose nucleic acid testing was negative or unavailable were later excluded from the analysis (N = 16). If RNA PCR was undetectable, human immunodeficiency virus (HIV) enzyme immunoassay (EIA) and western blot (WB) were performed. Those with negative or discordant EIA and WB were considered HIV negative and excluded from further analysis (N = 6). ART eligibility was assessed using age, CD4 count, and clinical HIV stage. Among 150 patients with HIV RNA PCR results, 15 had undetectable HIV RNA. Of those, EIA and WB were positive in nine patients and negative or discordant in six patients. PPV of serial RDT was 90% versus RNA PCR alone and 96% versus combined RNA PCR, EIA, and WB. Of all patients aged ≥ 5 years, 8.9% were ineligible for ART under previous WHO guidelines. Improved HIV testing algorithms are needed for accurate diagnosis of HIV infection in children as prevalence of pediatric HIV declines. Universal treatment will significantly increase the numbers of older children who qualify for ART.

Evaluation of the Bio-Rad Geenius HIV-1/2 test as a confirmatory assay

ObjectivesWe have evaluated the recently Conformité Européenne (CE)-marked Bio-Rad Geenius human immunodeficiency virus (HIV)1/2 as a rapid and simple alternative to western blot for confirmation of HIV screening results. MethodsA total of 160 serum samples were tested: 44 HIV-1 reactive samples by a fourth-generation Murex HIV Ag/Ab and/or Vidas HIV Duo Ultra, five HIV-2 reactive samples, 15 HIV-1 non-B subtype samples and 11 confirmed HIV-1 early seroconversion samples, 72 nonreactive samples, eight indeterminate samples by MP HIV BLOT 2.2 confirmed negative after follow-up and five low-reactive samples by enzyme immunoassay (EIA) negative by MP HIV BLOT 2.2. The samples were tested according to the manufacturer's guidelines. ResultsThe overall sensitivity for Bio-Rad Geenius HIV1/2 assay was 92%. Five out of 11 early seroconversion samples were tested positive, four negative and two indeterminate. All HIV-1 non-B subtype samples were tested positive. Two out of the five HIV-2 reactive samples were tested positive HIV-2, two positive HIV-2 with HIV-1 cross-reaction and one HIV positive untypable. After excluding early seroconversion samples, the sensitivity of Bio-Rad Geenius HIV1/2 assay reached 100%. Overall specificity was 96%. All HIV negative serums by fourth-generation EIA were tested negative. All five low-reactive samples by EIA, negative by HIV BLOT 2.2 were tested negative by Bio-Rad Geenius HIV1/2. Two out of the eight indeterminate samples by MP HIV BLOT 2.2 that were confirmed negative after follow-up were tested indeterminate and one invalid, the other five were negative. After excluding these last 13 samples, the specificity of Bio-Rad Geenius HIV1/2 assay reached 100%. In comparison with MP HIV BLOT 2.2, the Bio-Rad Geenius HIV1/2 assay was markedly time saving, allowed full traceability, automatic reading and interpretation. ConclusionsThe Bio-Rad Geenius HIV1/2 confirmatory system represents a reliable alternative to other confirmatory assays in HIV testing algorithms and provides clear improvement in quality management.

Evaluation of the Bio-Rad Geenius HIV-1/2 test as a confirmatory assay

a b s t r a c t Objectives: We have evaluated the recently Conformite Europeenne (CE)-marked Bio-Rad Geenius human immunodeficiency virus (HIV)1/2 as a rapid and simple alternative to western blot for confirmation of HIV screening results. Methods: A total of 160 serum samples were tested: 44 HIV-1 reactive samples by a fourth-generation Murex HIV Ag/Ab and/or Vidas HIV Duo Ultra, five HIV-2 reactive samples, 15 HIV-1 non-B subtype samples and 11 confirmed HIV-1 early seroconversion samples, 72 nonreactive samples, eight indeter- minate samples by MP HIV BLOT 2.2 confirmed negative after follow-up and five low-reactive samples by enzyme immunoassay (EIA) negative by MP HIV BLOT 2.2. The samples were tested according to the manufacturer's guidelines. Results: The overall sensitivity for Bio-Rad Geenius HIV1/2 assay was 92%. Five out of 11 early serocon- version samples were tested positive, four negative and two indeterminate. All HIV-1 non-B subtype samples were tested positive. Two out of the five HIV-2 reactive samples were tested positive HIV-2, two positive HIV-2 with HIV-1 cross-reaction and one HIV positive untypable. After excluding early sero- conversion samples, the sensitivity of Bio-Rad Geenius HIV1/2 assay reached 100%. Overall specificity was 96%. All HIV negative serums by fourth-generation EIA were tested negative. All five low-reactive samples by EIA, negative by HIV BLOT 2.2 were tested negative by Bio-Rad Geenius HIV1/2. Two out of the eight indeterminate samples by MP HIV BLOT 2.2 that were confirmed negative after follow-up were tested indeterminate and one invalid, the other five were negative. After excluding these last 13 samples, the specificity of Bio-Rad Geenius HIV1/2 assay reached 100%. In comparison with MP HIV BLOT 2.2, the Bio-Rad Geenius HIV1/2 assay was markedly time saving, allowed full traceability, automatic reading and interpretation. Conclusions: The Bio-Rad Geenius HIV1/2 confirmatory system represents a reliable alternative to other confirmatory assays in HIV testing algorithms and provides clear improvement in quality management. © 2014 Elsevier B.V. All rights reserved.

Assessment of Quality Assurance Program of HIV Testing in Ethiopia

Background: HIV/AIDS is one of the most challenging health crises facing the world today. The availability of excellent HIV (Human immunodeficiency virus) tests does not automatically guarantee reliable result. Many steps are involved between specimen collections to the moment when reported to physician and at each step something may go wrong. Measures to control the quality of result in HIV diagnostic laboratories are extremely important, because of the consequence of either false positive or false negative results are huge. Methods: A cross sectional study conducted to assess quality assurance program of HIV testing in Addis Ababa Hospitals and Clinics, Ethiopia from May to October 2012. A well designed and structured questionnaire, Checklist and onsite observation were used to collect data. Data was processed and analyzed with SPSS version16.0. Results: Out of 20 assessed hospitals and clinics cases, 3(14%) laboratory personnel’s who conduct HIV testing were found to have no training in HIV testing. Some laboratories 2 (10%) do not follow HIV testing algorithm and also 2 (10%) laboratory personnel’s do not know what to do in case of indeterminate result. HIV testing methods used were Rapid/ simple 20(100%), ELISA 13 (65%), and Western blot 1(5%). All laboratories use controls that are supplied with kit but 2 (10%) laboratories use external control (pooled sera) additionally. Seventeen (85%) uses manual (guidelines) supplied with kits but none of them uses SOPs (Standard operating procedures). There was poor participation in EQA (External Quality Assessment) program (50%). Conclusion: This study showed that there is lack of qualified human resources, not following HIV testing algorithm and poor participation in External quality assessment program. Therefore having a good quality assurance program and participation in external quality assessment scheme is indispensable. In addition, provision of refreshment training for laboratory personnel’s’ who conduct HIV testing and involving them in planning and management will increase the quality of HIV testing.

Evaluation of five simple rapid HIV assays for potential use in the Brazilian national HIV testing algorithm

Since 2005, the Department of Sexually Transmitted Diseases (STDs), Acquired Immunodeficiency Syndrome (AIDS) and Viral Hepatitis under the Health Surveillance Secretariat in Brazil's Ministry of Health has approved a testing algorithm for using rapid human immunodeficiency virus (HIV) tests in the country. Given the constant emergence of new rapid HIV tests in the market, it is necessary to maintain an evaluation program for them. Conscious of this need, this multicenter study was conducted to evaluate five commercially available rapid HIV tests used to detect anti-HIV antibodies in Brazil.The five commercial rapid tests under assessment were the VIKIA HIV-1/2 (bioMérieux, Rio de Janeiro, Brazil), the Rapid Check HIV 1 & 2 (Center of Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil), the HIV-1/2 3.0 Strip Test Bioeasy (S.D., Kyonggi-do, South Korea), the Labtest HIV (Labtest Diagnóstica, Lagoa Santa, Brazil) and the HIV-1/2 Rapid Test Bio-Manguinhos (Oswaldo Cruz Foundation, Rio de Janeiro, Brazil). A total of 972 whole-blood samples were collected from HIV-infected patients, pregnant women and individuals seeking voluntary counselling and testing who were recruited from five centers in different regions of the country. Informed consent was obtained from the study participants. The results were compared with those obtained using the HIV algorithm used currently in Brazil, which includes two enzyme immunoassays and one Western blot test. The operational performance of each assay was also compared to the defined criteria.A total of 972 samples were tested using reference assays, and the results indicated 143 (14.7%) reactive samples and 829 (85.3%) nonreactive samples. Sensitivity values ranged from 99.3 to 100%, and specificity was 100% for all five rapid tests. All of the rapid tests performed well, were easy to perform and yielded high scores in the operational performance analysis. Three tests, however, fulfilled all of the prerequisites established previously by the Department of STDs, AIDS and Viral Hepatitis: the HIV-1/2 3.0 Strip Test Bioeasy, the Rapid Check HIV 1 & 2 and the VIKIA HIV-1/2.Three of the five tests evaluated (the HIV-1/2 3.0 Strip Test Bioeasy, the Rapid Check HIV 1 and 2 and the VIKIA HIV-1/2) performed as well as the reference assays and fulfilled the requirements for use in the Brazilian national algorithm.

Enhanced U.S. Army HIV Diagnostic Algorithm Used to Diagnose Acute HIV Infection in a Deployed Soldier

Antibody screening alone may fail to detect human immunodeficiency virus (HIV) in recently infected individuals. By U.S. Army regulation, HIV-infected soldiers are not permitted to deploy to areas of conflict, including Iraq and Afghanistan. We report here the first case of acute HIV infection (AHI) in a soldier in a combat area of operation detected by an enhanced U.S. Army HIV testing algorithm and discuss features of the tests which aided in clinical diagnosis. We tested the sample from the AHI case with a third generation HIV-1/HIV-2 plus O enzyme immunoassay, HIV-1 Western Blot, and a qualitative HIV-1 ribonucleic acid molecular diagnostic assay. Risk factors for HIV acquisition were elicited in an epidemiologic interview. Evaluation of the blood sample for AHI indicated an inconclusive serologic profile and a reactive HIV-1 ribonucleic acid result. The main risk factor for acquisition reported was unprotected sexual intercourse with casual strangers in the U.S. while on leave during deployment. The clinical diagnosis of AHI in a combat area of operation is important. Diagnosis of HIV is key to preventing adverse effects to the infected soldier from deployment stressors of deployment and further transmission via parenteral or sexual exposures.

Large-Scale Human Immunodeficiency Virus Rapid Test Evaluation in a Low-Prevalence Ugandan Blood Bank Population

The use of rapid tests for human immunodeficiency virus (HIV) has become standard in HIV testing algorithms employed in resource-limited settings. We report an extensive HIV rapid test validation study conducted among Ugandan blood bank donors at low risk for HIV infection. The operational characteristics of four readily available commercial HIV rapid test kits were first determined with 940 donor samples and were used to select a serial testing algorithm. Uni-Gold Recombigen HIV was used as the screening test, followed by HIV-1/2 STAT-PAK for reactive samples. OraQuick HIV-1 testing was performed if the first two test results were discordant. This algorithm was then tested with 5,252 blood donor samples, and the results were compared to those of enzyme immunoassays (EIAs) and Western blotting. The unadjusted algorithm sensitivity and specificity were 98.6 and 99.9%, respectively. The adjusted sensitivity and specificity were 100 and 99.96%, respectively. This HIV testing algorithm is a suitable alternative to EIAs and Western blotting for Ugandan blood donors.

Detection of Acute Infections during HIV Testing in North Carolina

North Carolina has added nucleic acid amplification testing for the human immunodeficiency virus (HIV) to standard HIV antibody tests to detect persons with acute HIV infection who are viremic but antibody-negative. To determine the effect of nucleic acid amplification testing on the yield and accuracy of HIV detection in public health practice, we conducted a 12-month observational study of methods for state-funded HIV testing. We compared the diagnostic performance of standard HIV antibody tests (i.e., enzyme immunoassay and Western blot analysis) with an algorithm whereby serum samples that yielded negative results on standard antibody tests were tested again with the use of nucleic acid amplification. A surveillance algorithm with repeated sensitive-less-sensitive enzyme immunoassay tests was also evaluated. HIV infection was defined as a confirmed positive result on a nucleic acid amplification test or as HIV antibody seroconversion. Between November 1, 2002, and October 31, 2003, 109,250 persons at risk for HIV infection who had consented to HIV testing presented at state-funded sites. There were 606 HIV-positive results. Established infection, as identified by standard enzyme immunoassay or Western blot analysis, appeared in 583 participants; of these, 107 were identified, with the use of sensitive-less-sensitive enzyme immunoassay tests, as recent infections. A total of 23 acutely infected persons were identified only with the use of the nucleic acid amplification algorithm. With all detectable infections taken into account, the sensitivity of standard antibody testing was 0.962 (95 percent confidence interval, 0.944 to 0.976). There were two false positive results on nucleic acid amplification tests. The specificity and positive predictive value of the algorithm that included nucleic acid amplification testing were greater than 0.999 (95 percent confidence interval, 0.999 to >0.999) and 0.997 (95 percent confidence interval, 0.988 to >0.999), respectively. Of the 23 acute HIV infections, 16 were detected at sexually transmitted disease clinics. Emergency measures for HIV prevention protected 48 sex partners and one fetus from high-risk exposure to HIV. The addition of nucleic acid amplification testing to an HIV testing algorithm significantly increases the identification of cases of infection without impairing the performance of diagnostic testing. The detection of highly contagious, acutely infected persons creates new opportunities for HIV surveillance and prevention.

Accuracy and costs of rapid human immunodeficiency virus testing technologies in rural hospitals in Zambia.

To evaluate the accuracy and costs of newer rapid human immunodeficiency virus (HIV) antibody tests in primary health care settings in rural Zambia. Three rural hospitals participated in this study. During a baseline assessment period, HIV testing practices were recorded on 250 consecutive clients at each hospital. Baseline evaluation was compared with 250 subsequent consecutive clients tested using a testing algorithm consisting of an initial screening HIV Dipstick test (McDonald Scientific [PVT] Limited, Harare, Zimbabwe) followed by confirmatory testing of all reactive specimens using the HIV Capillus test (Cambridge Diagnostics, Galway, Ireland), in conformity with World Health Organization HIV testing recommendations. Quality control was performed at a national university teaching hospital laboratory. A total of 1,500 clients was entered, with an HIV seropositivity rate of 53.2%. Most HIV testing was performed on patients with signs and symptoms suggestive of HIV infection. Same-day results were provided for only 16%. The HIV Dipstick testing algorithm sensitivity was 96.9%, and specificity was 98.0%. Counselor dissatisfaction was greater with the Dipstick algorithm as a result of 5.3% discordant results. Use of the HIV Dipstick testing algorithm cost between US $3.00 and US $3.80 per client tested. The accuracy of HIV testing in unsophisticated rural laboratories in Zambia is acceptable. Although HIV Dipstick testing algorithm costs were relatively high for a developing country, this HIV testing procedure is currently the most economical method available in Zambia. Accurate, less costly HIV testing algorithms are still needed.

Evaluation of a human immunodeficiency virus test algorithm utilizing a recombinant protein enzyme immunoassay

Many truly human immunodeficiency virus (HIV) antibody-negative serum samples may be unnecessarily subjected to costly and time-consuming Western blots (immunoblots). An investigation was undertaken to evaluate the efficiency of using a recombinant protein-based enzyme immunosorbent assay (EIA; Cambridge BioScience [CBC] Recombigen HIV EIA) as an adjunct to whole viral lysate EIA. A total of 2,212 serum samples which had been screened by viral lysate EIA were tested by CBC EIA in parallel with the Western blot. The sensitivity and specificity of the CBC kit were 99.9 and 99.7%, respectively. Positive and negative predictive values were 99.7 and 99.9%, respectively. The high sensitivity of this kit and its high negative predictive value make it an attractive addition to an HIV testing algorithm by reducing the number of Western blot tests on truly antibody negative serum samples.