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AbstractIntroduction: Although individual HIV rapid diagnostic tests (RDTs) show good performance in evaluations conducted by WHO, reports from several African countries highlight potentially significant performance issues. Despite widespread use of RDTs for HIV diagnosis in resource‐constrained settings, there has been no systematic, head‐to‐head evaluation of their accuracy with specimens from diverse settings across sub‐Saharan Africa. We conducted a standardized, centralized evaluation of eight HIV RDTs and two simple confirmatory assays at a WHO collaborating centre for evaluation of HIV diagnostics using specimens from six sites in five sub‐Saharan African countries.Methods: Specimens were transported to the Institute of Tropical Medicine (ITM), Antwerp, Belgium for testing. The tests were evaluated by comparing their results to a state‐of‐the‐art reference algorithm to estimate sensitivity, specificity and predictive values.Results: 2785 samples collected from August 2011 to January 2015 were tested at ITM. All RDTs showed very high sensitivity, from 98.8% for First Response HIV Card Test 1–2.0 to 100% for Determine HIV 1/2, Genie Fast, SD Bioline HIV 1/2 3.0 and INSTI HIV‐1/HIV‐2 Antibody Test kit. Specificity ranged from 90.4% for First Response to 99.7% for HIV 1/2 STAT‐PAK with wide variation based on the geographical origin of specimens. Multivariate analysis showed several factors were associated with false‐positive results, including gender, provider‐initiated testing and the geographical origin of specimens. For simple confirmatory assays, the total sensitivity and specificity was 100% and 98.8% for ImmunoComb II HIV 12 CombFirm (ImmunoComb) and 99.7% and 98.4% for Geenius HIV 1/2 with indeterminate rates of 8.9% and 9.4%.Conclusions: In this first systematic head‐to‐head evaluation of the most widely used RDTs, individual RDTs performed more poorly than in the WHO evaluations: only one test met the recommended thresholds for RDTs of ≥99% sensitivity and ≥98% specificity. By performing all tests in a centralized setting, we show that these differences in performance cannot be attributed to study procedure, end‐user variation, storage conditions, or other methodological factors. These results highlight the existence of geographical and population differences in individual HIV RDT performance and underscore the challenges of designing locally validated algorithms that meet the latest WHO‐recommended thresholds.

AbstractIntroduction: We evaluated the diagnostic accuracy of HIV testing algorithms at six programmes in five sub‐Saharan African countries.Methods: In this prospective multisite diagnostic evaluation study (Conakry, Guinea; Kitgum, Uganda; Arua, Uganda; Homa Bay, Kenya; Doula, Cameroun and Baraka, Democratic Republic of Congo), samples from clients (greater than equal to five years of age) testing for HIV were collected and compared to a state‐of‐the‐art algorithm from the AIDS reference laboratory at the Institute of Tropical Medicine, Belgium. The reference algorithm consisted of an enzyme‐linked immuno‐sorbent assay, a line‐immunoassay, a single antigen‐enzyme immunoassay and a DNA polymerase chain reaction test.Results: Between August 2011 and January 2015, over 14,000 clients were tested for HIV at 6 HIV counselling and testing sites. Of those, 2786 (median age: 30; 38.1% males) were included in the study. Sensitivity of the testing algorithms ranged from 89.5% in Arua to 100% in Douala and Conakry, while specificity ranged from 98.3% in Doula to 100% in Conakry. Overall, 24 (0.9%) clients, and as many as 8 per site (1.7%), were misdiagnosed, with 16 false‐positive and 8 false‐negative results. Six false‐negative specimens were retested with the on‐site algorithm on the same sample and were found to be positive. Conversely, 13 false‐positive specimens were retested: 8 remained false‐positive with the on‐site algorithm.Conclusions: The performance of algorithms at several sites failed to meet expectations and thresholds set by the World Health Organization, with unacceptably high rates of false results. Alongside the careful selection of rapid diagnostic tests and the validation of algorithms, strictly observing correct procedures can reduce the risk of false results. In the meantime, to identify false‐positive diagnoses at initial testing, patients should be retested upon initiating antiretroviral therapy.

Our objective was to evaluate the performance of HIV testing algorithms based on WHO recommendations, using data from specimens collected at six HIV testing and counseling sites in sub-Saharan Africa (Conakry, Guinea; Kitgum and Arua, Uganda; Homa Bay, Kenya; Douala, Cameroon; Baraka, Democratic Republic of Congo). A total of 2,780 samples, including 1,306 HIV-positive samples, were included in the analysis. HIV testing algorithms were designed using Determine as a first test. Second and third rapid diagnostic tests (RDTs) were selected based on site-specific performance, adhering where possible to the WHO-recommended minimum requirements of ≥99% sensitivity and specificity. The threshold for specificity was reduced to 98% or 96% if necessary. We also simulated algorithms consisting of one RDT followed by a simple confirmatory assay. The positive predictive values (PPV) of the simulated algorithms ranged from 75.8% to 100% using strategies recommended for high-prevalence settings, 98.7% to 100% using strategies recommended for low-prevalence settings, and 98.1% to 100% using a rapid test followed by a simple confirmatory assay. Although we were able to design algorithms that met the recommended PPV of ≥99% in five of six sites using the applicable high-prevalence strategy, options were often very limited due to suboptimal performance of individual RDTs and to shared falsely reactive results. These results underscore the impact of the sequence of HIV tests and of shared false-reactivity data on algorithm performance. Where it is not possible to identify tests that meet WHO-recommended specifications, the low-prevalence strategy may be more suitable.

IntroductionWe studied factors associated with the continuum of HIV care in Belgium.MethodsData of the national registration of new HIV diagnosis and of the national cohort of HIV‐infected patients in care were combined to obtain estimates of and factors related with proportions of HIV‐infected patients in each step of the continuum of care from diagnosis to suppressed viral load (VL). Factors associated with ignorance of HIV seropositivity were analyzed among patients co‐infected with HIV and STI in the Belgian STI sentinel surveillance network. Associated factors were identified by multivariate logistic regression.ResultsAmong 4038 individuals diagnosed with HIV between 2007 and 2010, 90.3% were linked to care. Of 11684 patients in care in 2010, 90.8% were retained in care up to the following year, 88.3% of those were on ART, of whom 95.3% had suppressed VL (<500 cp/ml) (Figure 1). In multivariate analyses, factors associated with ignoring HIV+ status were being younger (p<0.001), being heterosexual compared to MSM, and of a region of origin other than Belgium, Sub‐Saharan Africa and Europe. Non‐Belgian regions of origin were associated with lower entry and retention in care (p<0.001 for both). Preoperative HIV testing was associated with lower entry in care (p=0.003). MSM had a higher retention in care (p<0.001), whilst IDU had lower retention (p=0.004). Low CD4 at first clinical contact and clinical reasons for HIV testing were independently associated with being on ART (p<0.001 for both); whilst prenatal HIV diagnosis was associated with lower proportion on ART (p=0.016) and lower proportion with suppressed VL among those on ART (p=0.005). Older age was associated with both being on ART and having suppressed VL among those on ART (p=0.007 and p<0.001 respectively), independently of time since HIV diagnosis (Table 1).ConclusionsRegions of origin and risk groups (MSM/heterosexual/IDU) are the main factors associated with ignorance of HIV seropositivity, entry and retention in care, but once the HIV patient is retained in care, no effect of these factors on the proportions on ART and with suppressed VL are observed. The association of prenatal HIV diagnosis and proportions on ART and with suppressed VL could be biased by transitory CD4 disturbances during pregnancy and ART discontinuation after pregnancy. The higher probabilities of older patients to be on ART and have suppressed VL once retained in care could be influenced by factors not studied here like comorbidities, adherence or duration on ART.

BACKGROUND: In the wake of the recent outbreak of Ebola virus disease (EVD) in several African countries, the World Health Organization prioritized the evaluation of treatment with convalescent plasma derived from patients who have recovered from the disease. We evaluated the safety and efficacy of convalescent plasma for the treatment of EVD in Guinea. METHODS: In this nonrandomized, comparative study, 99 patients of various ages (including pregnant women) with confirmed EVD received two consecutive transfusions of 200 to 250 ml of ABO-compatible convalescent plasma, with each unit of plasma obtained from a separate convalescent donor. The transfusions were initiated on the day of diagnosis or up to 2 days later. The level of neutralizing antibodies against Ebola virus in the plasma was unknown at the time of administration. The control group was 418 patients who had been treated at the same center during the previous 5 months. The primary outcome was the risk of death during the period from 3 to 16 days after diagnosis with adjustments for age and the baseline cycle-threshold value on polymerase-chain-reaction assay; patients who had died before day 3 were excluded. The clinically important difference was defined as an absolute reduction in mortality of 20 percentage points in the convalescent-plasma group as compared with the control group. RESULTS: A total of 84 patients who were treated with plasma were included in the primary analysis. At baseline, the convalescent-plasma group had slightly higher cycle-threshold values and a shorter duration of symptoms than did the control group, along with a higher frequency of eye redness and difficulty in swallowing. From day 3 to day 16 after diagnosis, the risk of death was 31% in the convalescent-plasma group and 38% in the control group (risk difference, -7 percentage points; 95% confidence interval [CI], -18 to 4). The difference was reduced after adjustment for age and cycle-threshold value (adjusted risk difference, -3 percentage points; 95% CI, -13 to 8). No serious adverse reactions associated with the use of convalescent plasma were observed. CONCLUSIONS: The transfusion of up to 500 ml of convalescent plasma with unknown levels of neutralizing antibodies in 84 patients with confirmed EVD was not associated with a significant improvement in survival. (Funded by the European Union's Horizon 2020 Research and Innovation Program and others; ClinicalTrials.gov number, NCT02342171.).

AbstractIdentity leadership captures leaders efforts to create and promote a sense of shared group membership (i.e., a sense of "we" and of "us") among followers. The present research report tests this claim by drawing on data from 26 countries that are part of the Global Identity Leadership Development (GILD) project to examine the relationship between political leaders' identity leadership and civic citizenship behavior (N = 6787). It also examines the contributions of trust and economic inequality to this relationship. Political leaders' identity leadership (PLIL) was positively associated with respondents' people‐oriented civic citizenship behaviors (CCB‐P) in 20 of 26 countries and civic citizenship behaviors aimed at one's country (CCB‐C) in 23 of 26 countries. Mediational analyses also confirmed the indirect effects of PLIL via trust in fellow citizens on both CCB‐P (in 25 out of 26 countries) and CCB‐C (in all 26 countries). Economic inequality moderated these effects such that the main and indirect effects of trust in one's fellow citizens on CCB‐C were stronger in countries with higher economic inequality. This interaction effect was not observed for CCB‐P. The study highlights the importance of identity leadership and trust in fellow citizens in promoting civic citizenship behavior, especially in the context of economic inequality.