HIV Testing Algorithm Research Articles

Lessons learnt from assessing and improving accuracy and positive predictive value of the national HIV testing algorithm in Nigeria.

HIV testing remains an entry point into HIV care and treatment services. In 2007, Nigeria adopted and implemented a two-test rapid HIV testing algorithm of three HIV rapid test kits, following the sequence: Alere Determine (first test), UnigoldTM (second test), and STAT-PAK® as the tie-breaker. Sub-analysis of the 2018 Nigeria HIV/AIDS Indicator and Impact Survey data showed significant discordance between the first and second tests, necessitating an evaluation of the algorithm. This manuscript highlights lessons learnt from that evaluation. A two-phased evaluation method was employed, including abstraction and analysis of retrospective HIV testing data from January 2017 to December 2019 from 24 selected sites supported by the United States President's Emergency Plan for AIDS Relief programme. A prospective evaluation of HIV testing was done among 2895 consecutively enrolled and consented adults, aged 15-64 years, accessing HIV testing services from three selected sites per state across the six geopolitical zones of Nigeria between July 2020 and September 2020. The prospective evaluation was performed both in the field and at the National Reference Laboratory under controlled laboratory conditions. Stakeholder engagements, strategic selection and training of study personnel, and integrated supportive supervision were employed to assure the quality of evaluation procedures and outcomes. The algorithm showed higher sensitivity and specificity in the National Reference Laboratory compared with the field. The approaches to quality assurance were integral to the high-quality study outcomes. We recommend comparison of testing algorithms under evaluation against a gold standard. This study provides context-specific considerations in using World Health Organization recommendations to evaluate the Nigerian national HIV rapid testing algorithm.

Suppressed HIV antibody responses following exposure to antiretrovirals—evidence from PrEP randomized trials and early antiretroviral treatment initiation studies

BackgroundExposure to antiretrovirals at or early after HIV acquisition can suppress viral replication and blunt antibody (Ab) responses; a reduced HIV detectability could impact diagnosis and blood donation screening. MethodsWe used three antigen (Ag)/Ab assays and one nucleic acid test (NAT) to analyze samples collected in pre-exposure prophylaxis (PrEP) trials (iPrEx; Partners PrEP) before infection detection by Ab-only rapid diagnostic tests (RDTs), and in early antiretroviral treatment (ART) initiation studies (RV254; SIPP). ResultsReactivity using NAT and Ag/Ab assays in samples collected up to 8 weeks prior to the first reactive RDT from 251 PrEP trials participants varied between 49-61% for active PrEP users and between 27-37% for placebo users. Among RV254 participants, reactivity in Ag/Ab assays was <100% at all timepoints, and lower among those initiating ART earlier. Seroreversions occurred for 29% (16/55), and blood donation screening with NAT and Ag/Ab assays could have missed up to 36% (20/55) of RV254 participants. For SIPP participants, who started ART at later timepoints, Ag/Ab assays identified infections with no evidence of reactivity waning. ConclusionPrEP and early ART initiation can delay or reduce HIV detectability. Considerations for the implementation of NAT and Ag/Ab tests in PrEP/PEP programs relying on Ab-only RDTs should be balanced according to feasibility and public health impact. While blood transfusion services using Ab-only RDTs for HIV screening should adopt higher sensitivity tests, surveillance and further research are needed to determine the need for novel HIV testing algorithms for those already using NAT and Ag/Ab screening assays.

HIV Diagnostic Algorithms in A Resource-Limited Setting: A Comparative Study

Background: Adoption of appropriate HIV testing algorithm is essential for quality HIV diagnostic results. Whether rapid enzyme immunoassay (rEIA) or combination of rapid enzyme immunoassay and enzyme-linked immunosorbent assay (rEIA-ELISA) alternative confirmatory algorithm is enough to make accurate HIV diagnosis has been a subject of controversies. Recent evaluation of national algorithm for HIV testing presented some discrepancies in results. Again, current guideline prescribed discontinuity of Western blot supplemental test and its replacement with Geenius HIV-1/ HIV-2 differentiation test followed by nucleic acid testing. The objective of this study is to compare HIV-1 testing algorithms using ELISA-NAT algorithm as the gold standard for HIV-1 diagnosis, and rEIA-Western blot and ELISA-Western blot as alternative confirmatory algorithms for HIV-2 diagnosis. Methods: This is a comparative study involving a cohort of 173 (98.9%) HIV-positive subjects and two (1.1%) HIV-negative subjects initially diagnosed on the basis of rEIA algorithm. Plasma samples separated from ethylene diamine tetra-acetic acid anticoagulated blood were used for further analyses. Fourth generation HIV antigen-antibody kit was used for further testing to make up rEIA-ELISA algorithm. Analyses with Western blot 1 and 2 assays were done as supplemental tests to make up alternative rEIA-Western blot and ELISA-Western blot confirmatory algorithms. Research subjects were further tested for HIV-RNA under PEPFAR plan. The sensitivity, specificity, positive predictive value and negative predictive value of algorithms were compared using the descriptive statistics of the SPSS version 17. Results: The HIV testing analyses showed 100% sensitivity, specificity, positive predictive value and negative predictive value from algorithm to algorithm especially for HIV-1 diagnosis. Use of combined ELISA-NAT confirmatory algorithm validated outcomes of rEIA-Western blot and ELISA-Western blot alternative confirmatory algorithms for HIV-1 diagnosis. Among HIV-1 positive samples tested, 50.0-60.7% HIV-2 Western blot indeterminate result was obtained and 7.1-10.7% HIV-1/HIV-2 co-infections were observed. Conclusion: The rEIA or national algorithm and its combination with enzyme-linked immunosorbent assay are reliable alternative confirmatory algorithms for the diagnosis of established HIV-1infection in resource-limited settings but not for HIV-2. Diagnosing acute HIV infection with current algorithm is limited and still require further review.

High Prevalence of Unconfirmed Positive HIV PCR Test Results among African Infants with HIV Exposure in the International epidemiology Databases to Evaluate AIDS (IeDEA) Consortium.

In a large, multi-regional cohort of African infants with HIV exposure, 44% of those with a positive HIV PCR lacked a confirmatory positive test. Efforts are needed to ensure high-fidelity implementation of HIV testing algorithms, so that all positive results are confirmed thereby reducing the risk of potentially false-positive results.

Trends and predictors of unmet need for family planning among women living with HIV in Zambia: implications for elimination of vertical transmission of HIV

BackgroundPrevention of vertical (mother to child) transmission of HIV is one of the key strategies towards HIV epidemic control. Despite considerable progress over the past decade in Zambia, the country is yet to reach global and national target for elimination of vertical transmission of HIV. Avoidance of unintended pregnancy among women living with HIV is one of the cost-effective interventions in a comprehensive approach to prevent vertical transmission of HIV. Therefore, this study aimed at ascertaining trends in and predictors of unmet need for family planning among women living with HIV in Zambia.MethodsThe study employed a repeated cross sectional (RCS) study design, using data from the three (3) most recent consecutive rounds of the Zambia Demographic and Health Survey (ZDHS) conducted in 2007, 2013/2014 and 2018. The study used data from a total of 27,153 women aged 15–49 years over the three survey periods among whom 4,113 had an HIV positive result following a rigorous HIV testing algorithm of the demographic and health surveys, and these constituted our sample size of women living with HIV. We used descriptive statistics and logistic regression analyses to respectively ascertain trends in and predictors of unmet need for family planning among women living with HIV.ResultsOver the three survey points, unmet need for family planning among women living with HIV has largely remained unchanged from 20.8% in 2007 to 20.5% in 2013/14 and 21.1% in 2018 DHS. Residence, age of women, household wealth, woman’s parity, employment, and age of spouse emerged as significant predictors of unmet need for family planning among women living with HIV in Zambia.ConclusionPreventing HIV infection in a child preserves life, contributes to improving quality of life from its early stages and averts lifetime costs of HIV treatment and associated healthcare costs. There is need to consider optimization of interventions to prevent vertical transmission of HIV including shaping programming regarding preventing unintended pregnancies among women living with HIV. Among other aspects, policy and practice need to strengthen SRH/HIV integration and better target rural residents, younger women, those with high parity and consider positive male engagement to reduce unmet need for family planning among women living with HIV.

Верифікація алгоритмів тестування на ВІЛ з використанням швидких тестів

Верифікація алгоритмів тестування на ВІЛ з використанням швидких тестів

Using signal-to-cutoff ratios of HIV screening assay to predict HIV infection

BackgroundThe sensitivity of HIV screening assays often leads to a high rate of false-positive results, requiring retests and confirmatory tests. This study aimed to analyze the capability of signal-to-cutoff (S/CO) ratios of HIV screening assay to predict HIV infection.MethodsA retrospective study on the HIV screening-positive population was performed at Zhongshan Hospital, Xiamen University, the correlation between HIV screening assay S/CO ratios and HIV infection was assessed, and plotted Receiver Operating Characteristic (ROC) curves were generated to establish the optimal cutoff value for predicting HIV infection.ResultsOut of 396,679 patients, 836 were confirmed to be HIV-infected, with an HIV prevalence of 0.21%. The median S/CO ratios in HIV infection were significantly higher than that in non-HIV infection (296.9 vs. 2.41, P < 0.001). The rate of confirmed HIV infection was increased with higher S/CO ratios in the screening assay. The ROC curve based on the HIV screening assay S/CO ratio achieved a sensitivity of 93.78% and a specificity of 93.12% with an optimal cutoff value of 14.09. The area under the ROC curve was 0.9612. Further analysis of the ROC curve indicated that the S/CO ratio thresholds yielding positive predictive values of 99%, 99.5%, and 100% for HIV infection were 26.25, 285.7, and 354.5, respectively.ConclusionUsing HIV screening assay S/CO ratio to predict HIV infection can largely reduce necessitating retests and confirmatory tests. Incorporating the S/CO ratio into HIV testing algorithms can have significant implications for medical and public health practices.

Country adoption of WHO 2019 guidance on HIV testing strategies and algorithms: a policy review across the WHO African region

ObjectivesIn 2019, the WHO released guidelines on HIV testing service (HTS). We aim to assess the adoption of six of these recommendations on HIV testing strategies among African countries.DesignPolicy review.Setting47...

Measuring the performance of HIV self-testing at private pharmacies in Kenya: a cross-sectional study.

HIV self-testing (HIVST) has the potential to support daily oral pre-exposure prophylaxis (PrEP) delivery in private pharmacies, but many national guidelines have not approved HIVST for PrEP dispensing. In Kenya, pharmacy providers are permitted to deliver HIVST, but often do not have the required certification to deliver rapid diagnostic testing (RDT). We estimated the performance of provider-delivered HIVST compared to RDT, the standard of care for PrEP delivery, at private pharmacies in Kenya to inform decisions on the use of HIVST for PrEP scale-up. At 20 pharmacies in Kisumu County, we trained pharmacy providers (pharmacists and pharmaceutical technologists) on blood-based HIVST use and client assistance (if requested). We recruited pharmacy clients purchasing sexual and reproductive health-related products (e.g. condoms) and enrolled those ≥18 years with self-reported behaviours associated with HIV risk. Enrolled clients received HIVST with associated provider counselling, followed by RDT by a certified HIV testing services (HTS) counsellor. Pharmacy providers and clients independently interpreted HIVST results prior to RDT (results interpreted only by the HTS counsellor). We calculated the sensitivity and specificity of pharmacy provider-delivered HIVST compared to HTS counsellor-administered RDT. Between March and June 2022, we screened 1691 clients and enrolled 1500; 64% (954/1500) were female and the median age was 26 years (IQR 22-31). We additionally enrolled 40 providers; 42% (17/40) were pharmacy owners and their median years of experience was 6 (IQR 4-10). The majority (79%, 1190/1500) of clients requested provider assistance with HIVST and providers spent a median of 20 minutes (IQR 15-43) with each HIVST client. The sensitivity of provider-delivered HIVST at the pharmacy was high when interpreted by providers (98.5%, 95% CI 97.8%, 99.1%) and clients (98.8%, 95% CI 98.0%, 99.3%), as was the specificity of HIVST in this setting (provider-interpretation: 96.9%, 95% CI 89.2%, 99.6%; client-interpretation: 93.8%, 95% CI 84.8%, 98.3%). When compared to the national HIV testing algorithm, provider-delivered blood-based HIVST at private pharmacies in Kenya performed well. These findings suggest that blood-based HIVST may be a useful tool to support PrEP initiation and continuation at private pharmacies and potentially other community-based delivery settings.

Assessment of the performance regarding confirmatory diagnosis and initiation of antiretroviral therapy under a modified national HIV testing algorithm and pay-for-performance program in Taiwan

BackgroundA pay-for-performance plan for rapid antiretroviral therapy (ART) commencement was initiated in 2018, while a modified testing algorithm offers immunochromatographic test (ICT) to replace Western blot (WB), and simultaneous testing with ICT and Nucleic Acid Amplification Test (NAAT) for HIV-positive sera was adopted in 2019 in Taiwan. MethodsSerum specimens collected from 1117 suspected or confirmed HIV infection cases in 2016–2019 were reassessed the performance of WB, ICT, and NAAT. We reviewed the medical records of 10,732 individuals diagnosed with HIV in 2015–2021 to determine the time from screening to confirmatory diagnosis, followed by ART commencement. ResultsAll 860 WB-positives were also positive by ICT and NAAT. The positive detection percentages were 37.0% by ICT and 51.4% by NAAT for 257 WB-indeterminate and -negative sera. The sensitivity for WB and ICT was 93.8% and 95.5%, respectively. In the people living with HIV (PLHIV) cohort, the median time from initial positive to confirmatory diagnosis decreased from 5 to 6 days before 2019 to 1 day in 2021. The median time from initial positive to ART initiation decreased from 37 days in 2015, 14 days in 2018, to 6 days in 2021. Compared to 2015–2017, the time to ART initiation was 91.48 days lower in 2018 (P < 0.001) and 100.66 days lower in 2019–2021 (P < 0.001) by the adjusted linear regression model. ConclusionA significant decrease in the time to ART initiation was observed after initiation of the pay-for-performance program and optimized testing algorithm in Taiwan.

Evaluating the impact of point-of-care HIV viral load assessment on linkage to care in Baltimore, MD: a randomized controlled trial

BackgroundIntegration of a sensitive point-of-care (POC) HIV viral load (VL) test into screening algorithms may help detect acute HIV infection earlier, identify people with HIV (PWH) who are not virally suppressed, and facilitate earlier referral to antiretroviral therapy (ART), or evaluation for pre-exposure prophylaxis (PrEP). This report describes a randomized clinical trial sponsored by the Centers for Disease Control and Prevention (CDC): “Ending the HIV Epidemic Through Point-of-Care Technologies” (EHPOC). The study’s primary aim is to evaluate the use of a POC HIV VL test as part of a testing approach and assess the impact on time to linkage to ART or PrEP. The study will recruit people in Baltimore, Maryland, including patients attending a hospital emergency department, patients attending an infectious disease clinic, and people recruited via community outreach. The secondary aim is to evaluate the performance characteristics of two rapid HIV antibody tests approved by the United States Food and Drug Administration (FDA).MethodsThe study will recruit people 18 years or older who have risk factors for HIV acquisition and are not on PrEP, or PWH who are not taking ART. Participants will be randomly assigned to either the control arm or the intervention arm. Participants randomized to the control arm will only receive the standard-of-care (SOC) HIV screening tests. Intervention arm participants will receive a POC HIV VL test in addition to the SOC HIV diagnostic screening tests. Follow up will consist of an interim phone survey conducted at week-4 and an in-person week-12 visit. Demographic and behavioral information, and oral fluid and blood specimens will be collected at enrollment and at week-12. Survey data will be captured in a Research Electronic Data Capture (REDCap) database. Participants in both arms will be referred for either ART or PrEP based on their HIV test results.DiscussionThe EHPOC trial will explore a novel HIV diagnostic technology that can be performed at the POC and provide viral assessment. The study may help inform HIV testing algorithms and contribute to the evidence to support same day ART and PrEP recommendations.Trial registrationNIH ClinicalTrials.gov NCT04793750. Date: 11 March 2021.

Adherence to Current HIV Testing Protocols in the Northwest Region of Cameroon: Facilitators and Barriers

Prior to the release of the current HIV testing recommendation on retesting for verification (RFV), the Cameroon Baptist Convention Health Services (CBCHS) established 0.5% misdiagnosis and inappropriate ART treatment among ART clients in Northwest and Southwest regions. This study aimed at assessing adherence to HIV testing guideline and issues involved. This cross-sectional study was conducted at 27 purposefully selected sites where participants consented and anonymously completed a questionnaire containing questions on their knowledge and practice on RFV, challenges and facilitators. Records of clients who tested HIV positive in 2021 were reviewed to confirm RFV. Data was analysed for frequencies and proportions. A total of 25(93.6%) facilities had the minimum two laboratory staff, most (93.8%) had a minimum training at diploma level and had two or more years of work experience (91.7%). The staff knowledge was averagely 81% accurate on HIV testing algorithm, 79% on RFV and 63% on practice. The main facilitators of RFV were availability of rapid test kits (46%) and trained staff (10%) while bottlenecks were limited test kits (34%) and refusals (28%). Second event testing was performed for 92.5% (1525) of cases, of whom 93.4% was by another tester. Most independent testers knew the results of the first event test before conducting the second event test. Cases of documentation of second event testing without conducted it were reported. Staff were trained and knowledgeable on RFV, but the practice was low. More training and supervision are required for improvement on adherence to protocols for RFV. Keywords: ART, Adherence, Misdiagnosis, Retesting for verification, PMTCT.

Implementation of an HIV RNA Qualitative PCR Assay in an HIV Diagnostic Algorithm: A Single-Institution Experience.

Boston Medical Center (BMC) is a private, not-for-profit 514-bed academic medical center and legacy safety net hospital serving a diverse global patient population. BMC recently implemented a new HIV-1/HIV-2 Qualitative RNA PCR (HIV RNA QUAL) cleared by the US Food and Drug Administration to (1) replace antibody discrimination follow-up testing after a reactive fourth-generation (4G) serology screen and (2) use as a stand-alone diagnostic for suspected seronegative acute HIV infection. This report summarizes the results of a production monitor for the first 3 months postimplementation. The monitor characterized test utilization, diagnostic turnaround time, impact on send-out testing, results reflexed to HIV RNA discrimination follow-up, and discrepancies between screening and HIV RNA results that necessitated additional investigation. Another element was the novelty of using HIV RNA QUAL while awaiting the existing Centers for Disease Control and Prevention HIV testing algorithm update. The 4G screening components and the HIV RNA QUAL were also used to create an algorithm specific to and compliant with current guidelines for screening patients on HIV preexposure prophylaxis. Based on our findings, this new test algorithm may be reproducible and instructive at other institutions.

Lipid Profile and Cd4+ - T – Lymphocytes Counts in Naïve Human Immunodeficiency Virus Infected Pre – Menopausal Females.

This study was aimed at determining the serum lipid levels in naive HIVinfected pre – menopausal females and in the progression of HIV/AIDS. In a bid to determine lipid abnormalities or otherwise in naïve HIV – infected pre-menopausal females, 80 HIV- positive females aged between twenty to thirty five years at the PEPFAR, HIV clinic, University of Nigeria Teaching Hospital(UNTH), Enugu and 80 apparently healthy non-HIV positive agematched female volunteers that served as the control group were studied. The medical Ethical Committee of the UNTH, Ituku-Ozalla, Enugu, approved the study protocol and the patients’ informed consents were obtained prior to sample collection. The blood samples were collected using standard methods. HIV re-screening and confirmation were carried out using WHO HIV test algorithm. Automated method using Flow cytometry was used for the enumeration of CD4+ T Lymphocytes while lipid profile of the test subjects and the control group were carried out using standard methods. The results were expressed as mean ± standard deviation. The data were analyzed using graph pad Instat version 3.01, Graph pad software, San Diego, California, USA. The test of significance was based on probability (p) values of &lt; 0.05. Comparisons between groups were performed using One-way-ANOVA, Bonferroni’s multiple comparison test and student ttests depending on the number of variables. Serum total cholesterol, HDL and LDL levels of the patients were significantly lower (P &lt; 0.05) than the control groups and all decreased progressively with the progression of HIV/AIDS. However, triacylglylerols and VLDL levels were significantly higher (P &lt; 0.05) than the controls and all increased with the progression of HIV/AIDS.

2067. Missed Opportunities for Confirmatory HIV Testing at a Midwestern Medical Center

Abstract Background The currently recommended HIV testing algorithm begins with a 4th generation antigen/antibody (Ag/Ab) combination immunoassay, which allows for early detection of HIV. However, this assay’s high sensitivity can result in false positives that must be distinguished from acute infections via an HIV nucleic acid test (NAT). At our medical center, HIV NATs are recommended in the lab report for anyone with a positive p24Ag component on the screening assay, but they are not done reflexively by the lab as it requires a different blood tube. Thus, difficulties arise in obtaining the NAT, such as providers failing to order the test or patients failing to return for another blood draw, jeopardizing the diagnosis of early HIV. Methods We conducted a retrospective chart review of adult patients at a Midwest academic medical center with a positive p24Ag on the HIV-1/2 Ag/Ab combination assay between Jan. 1, 2017 and Feb. 21, 2021. We assessed if appropriate confirmatory testing was performed, identified barriers to missed opportunities for confirmatory testing, and used t-tests and Fisher’s exact tests to evaluate differences between those who did and did not receive confirmatory testing. Results Of 37 people with a positive p24Ag on the HIV Ag/Ab immunoassay, 6 (17%) did not have an HIV NAT performed within 30 days of their positive screening test. Of these 6 cases, the ordering provider did not acknowledge the need for a confirmatory test in 3 cases, the patient did not return for the test in 1 case, and other factors prevented follow-up in 2 cases. Of those who had an HIV NAT ordered, 7 (23%) had a positive HIV NAT. Younger age was significantly associated with completion of appropriate confirmatory testing (p=0.05), but other factors including sex, race, insurance status, having a primary care provider, specialty of ordering provider, encounter location, and test indication were not. Conclusion Our review identified multiple missed opportunities for confirmatory HIV testing following a positive p24Ag component on the HIV screening test. Provider lack of knowledge/awareness of the need for appropriate testing was the most common barrier. A quality improvement initiative will be undertaken to minimize future risk of missed opportunities for confirmatory testing. Disclosures Paul D. Fey, PhD, BioFire: Advisor/Consultant|BioFire: Grant/Research Support|Merck: Grant/Research Support Sara H. Bares, MD, Gilead Sciences: Expert Testimony|GSK ViiV Healthcare: Grant/Research Support|Janssen: Grant/Research Support.

Long-acting injectable cabotegravir for PrEP: A game-changer in HIV prevention?

Long-acting injectable cabotegravir (CAB-LA) represents a new additional option for HIV prevention in people at substantial risk of HIV infection that may fill the gaps in pre-exposure prophylaxis (PrEP) uptake, adherence, and retention in users having difficulty with oral PrEP. Data from clinical trials demonstrated that CAB-LA was safe, highly effective, and well-accepted for HIV prevention. However, the occurrence of breakthrough HIV infections despite timely injections, HIV seroconversion timing and patterns, risk of selection and dissemination of resistance-associated mutations to integrase inhibitors, complexity of follow-up, logistical considerations, and its cost effectiveness compared with oral PrEP constitute significant issues for the integration of CAB-LA into clinical routine. These concerns need to be addressed before moving forward with large-scale implementation programmes. Pilot and implementation projects are required in the following areas: HIV testing algorithms, patient education, clinic procedures, protocols for switching and discontinuation, efficacy and safety in populations not included in clinical trials, and demedicalization processes. The development of models to increase the uptake of, adherence to, and persistence with and after CAB-LA injections will also be of paramount importance for success. Lessons learned from these projects will increase experience, staff expertise, and organizational and training capacities to support the roll-out of this new agent as part of HIV prevention programmes. CAB-LA has not yet achieved its full potential in HIV prevention, and strong commitment from all stakeholders is required to push CAB-LA as a game-changer in HIV response.

Performance of HIV rapid testing algorithm in Nigeria: Findings from a household-based Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS).

The Nigeria AIDS Indicator and Impact Survey (NAIIS), a cross-sectional household survey, was conducted in 2018 with primary objectives to estimate HIV prevalence, HIV-1 incidence, and status of UNAIDS 90-90-90 cascade. We conducted retrospective analysis of the performance of HIV rapid tests and the national HIV testing algorithm used in Nigeria. The national algorithm included Determine HIV-1/2 as test 1 (T1), Unigold HIV-1/2 as test 2 (T2), and StatPak HIV-1/2 as the tie-breaker test (T3). Individuals reactive with T1 and either T2 or T3 were considered HIV-positive. HIV-positive specimens from the algorithm were further confirmed for the survey using supplemental test Geenius HIV-1/2. If Geenius did not confirm HIV-positive status, HIV-1 Western blot was performed. We calculated the concordance between tests and positive predictive value (PPV) of the algorithm on unweighted data. Of 204,930 participants (ages ≥18 months) 5,103 (2.5%) were reactive on T1. Serial testing of T1 reactive specimens with T2 or if needed by tiebreaker T3 identified 2958 (1.44%) persons as HIV-positive. Supplemental testing confirmed 2,800 (95%) as HIV-positive (HIV-1 = 2,767 [98.8%]; HIV-2 = 5 [0.2%]; dual infections = 22 [0.8%]). Concordance between T1 and T2 was 56.6% while PPV of the national algorithm was 94.5%. Our results show high discordant rates and poor PPV of the national algorithm with a false-positive rate of about 5.5% in the NAIIS survey. Considering our findings have major implications for HIV diagnosis in routine HIV testing services, additional evaluation of testing algorithm is warranted in Nigeria.

Vaccine-Induced Seroreactivity Impacts the Accuracy of HIV Testing Algorithms in Sub-Saharan Africa: An Exploratory Study.

The detection of vaccine-induced HIV antibody responses by rapid diagnostic tests (RDTs) may confound the interpretation of HIV testing results. We assessed the impact of vaccine-induced seroreactivity (VISR) on the diagnosis of HIV in sub-Saharan Africa. Samples collected from healthy participants of HIVIS and TaMoVac HIV vaccine trials after the final vaccination were analyzed for VISR using HIV testing algorithms used in Mozambique and Tanzania that employ two sequential RDTs. The samples were also tested for VISR using Enzygnost HIV Integral 4 ELISA and HIV western blot assays. Antibody titers to subtype C gp140 were determined using an in-house enzyme-linked immunosorbent assay (ELISA). The frequency of VISR was 93.4% (128/137) by Enzygnost HIV Integral 4 ELISA, and 66.4% (91/137) by western blot assay (WHO interpretation). The proportion of vaccine recipients that would have been misdiagnosed as HIV-positive in Mozambique was half of that in Tanzania: 26.3% (36/137) and 54.0% (74/137), respectively, p < 0.0001. In conclusion, the HIV RDTs and algorithms assessed here will potentially misclassify a large proportion of the HIV vaccine recipients if no other test is used. Increased efforts are needed to develop differential serological or molecular tools for use at the point of care.

Performance characteristics of two new rapid HIV diagnostic assays and use of test band reader

PurposeAccurate HIV diagnosis is essential for appropriate patient care. This present study evaluated the performance of two different new rapid HIV diagnostic tests; 1) TRUSTline HIV-1/2 Ab rapid test (Athenese-DxPvt. Ltd, Chennai, India)and 2) OnSite HIV 1/2 Ab Plus Combo Rapid Test (CTK Biotech Inc., San Diego, USA) and also validated ALTA Rapid Test Reader (RTR-1) (CTK Biotech Inc., San Diego, USA), the device is a user-friendly and image-analysis based qualitative/semi-quantitative tabletop reader. MethodsA total of n ​= ​500 characterized specimens were used for this evaluation and the results of the new test kits (TRUSTline and OnSite) were also compared with 4th generation ELISA kit (Genescreen™Ultra HIV Ag-Ab ELISA) and 3 other commercially available rapid tests that were in the market; 1)SD Bioline™ HIV 1/2 3.0, 2) Aspen® HIV 1/2 Rapid Ab Test and 3) Diagnostic enterprises HIVTRI-DOT. The test band intensities of the TRUSTline and OnSite tests were measured in an ALTA rapid test reader and compared with the naked eye reading. ResultsThe sensitivity, specificity, positive predictive value, negative predictive value and efficacy of TRUSTline and OnSite were 100%, 99.6%, 99.5%, 100% and 99.8% and 100%, 100%, 100%, 100% and 100% respectively. ConclusionsThe ‘TRUSTline HIV-1/2’ and ‘OnSite HIV 1/2' kits are suitable to use in the HIV testing algorithm. Use of the ALTA rapid test reader could be user's friendly in the field level testing in resource-limited settings”.

Prevalence of HIV and Its Co-Infection with Hepatitis B/C Virus Among Chronic Liver Disease Patients in Ethiopia.

BackgroundThe efficient use of antiretroviral drugs has significantly reduced AIDS-related morbidities and mortalities; however, mortality due to non-AIDS-related end-stage liver diseases is escalating in those living with HIV.ObjectiveThe study was designed to determine the prevalence of HIV and its co-infection with HBV and HCV among chronic liver disease (CLD) patients in Ethiopia.MethodsThree hundred and forty-five CLD patients were included in this study in two groups: Hepatocellular carcinoma (HCC) (n=128) and non-HCC (n=217) patients. The non-HCC group comprised patients with advanced liver disease (n=98) and chronic hepatitis (n=119). Enzyme immunoassays were used to determine HBV and HCV infection markers. In addition, a serial rapid HIV testing algorithm was employed to screen HIV infection.ResultsRegardless of the stage of liver disease, the overall frequency of HIV was 4.3% (15/345), with a 2% (7/345) and 0.3% (1/345) of HIV/HBV and HIV/HCV co-infection rate. Of all HIV-infected patients (n=15), 46.7% (7/15) and 6.7% (1/15) were co-infected with HBV (HBsAg+HBcAb+) and HCV (anti-HCV+ HCV-RNA+), respectively, and 86.7% (13/15) exhibited a marker of HBV exposure (total HBcAb+). Overall, the frequency of HIV and its co-infection with HBV was more noticeable among HCC than non-HCC patients [8.6% (11/128) vs 1.8 (4/217), p=0.005 and 3.9% (5/128) vs 0.9% (2/217), p=0.1]. The rate of HIV mono-infection was 3.9% (5/128) vs 0.9% (2/217) among HCC and non-HCC patients.ConclusionThe frequency of HIV and its co-infections with HBV/HCV exhibited an increasing pattern with the severity of the liver disease. Thus, screening all HIV-positive patients for HBV and HCV infection and all CLD patients for HIV infection and taking necessary preventive measures would be an essential strategy to prevent the progression of CLD and death related to liver disease in people living with HIV.