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Background. Hepatitis B virus (HBV) infection is a leading cause of liver disease worldwide. Hepatitis B surface antigen (HBsAg) rapid diagnostic tests (RDTs) could be an ideal tool for a large-scale HBV screening in settings with high endemicity but limited infrastructure. The aim of this study was to evaluate the diagnosis performance of such RDTs for screening HBV infection in Ivory Coast. Methods. From September 2018 to January 2019, a cross-sectional phase I evaluation study of RDTs was conducted in three laboratories of Abidjan (CeDReS, CNTS and IPCI), on a panel of 405 whole blood samples and 699 plasmas. Four HBsAg RDTs (Determine™ HBsAg, SD Bioline HBsAg WB®, Standard Q HBsAg® and Vikia HBsAg®) were evaluated. The diagnostic performance (sensitivity and specificity) was calculated in comparison to the reference sequential algorithms of two EIA tests (Dia.Pro HBsAg® one version ULTRA and Monolisa™ HBsAg ULTRA). Results. The Determine™ HBsAg and Vikia HBsAg® tests performed well, with 100% of sensitivity, specificity both on plasma and on whole blood. For SD Bioline HBsAg WB® and Standard Q HBsAg®, the specificities were 99.8% and the sensitivities 99.3% and 97.1% respectively. Finally, there were a total of 19 false negative results: 3 with SD Bioline HBsAg WB® and 16 with Standard Q HBsAg®. Conclusion. Determine HBsAg® from Alere and Vikia HBsAg® from Biomérieux are the most suitable RDTs for screening for HBV in Ivory Coast. A phase II evaluation must be initiated.

Dried Blood Spots (DBS) are blood collection carriers that facilitate the storage and transport of samples. Used for quality control during sero-epidemiological investigations, DBS eluate are not the conventional specimen indicated by manufacturers for enzyme immunoassay method (EIA) for hepatitis B virus surface (HBs antigen). The aim of our study was to evaluate DBS eluates used as a matrix for EIA of HBs antigen in a reference laboratory. This study took place from August 2016 to November 2017 at the Centre for Diagnosis and Research on AIDS and other infectious diseases (CeDReS) in Abidjan, Côte d'Ivoire. We used a panel of 149 whole blood samples from blood donors. The DBS performed with these samples were analyzed after elution with the HBsAg (version ULTRA) ELISA, Dia.Pro Diagnostic Bioprobes S.R.L., Sesto San Giovanni, Italy. The technical performance (sensitivity and specificity and kappa coefficient) of the test performed on DBS was determined for different ratios (optical density/threshold value) compared to the results obtained on the plasma used as reference. We obtained a sensitivity of 100% with DBS for all ratios. The specificity increased according to the ratio of optical density of the individual EIA reaction to the threshold value, with 6.09%, 47.0%, and 83.0%, respectively, for ratios of 1.0, 3.0, and 5.0. Best performance was observed at ratio of 10.0 with a sensitivity and specificity of 100%. In conclusion, DBS eluate can be used for the diagnosis of viral hepatitis B and would be useful for conducting sero-epidemiological investigations. However, ratio giving best performance must be determined for each enzyme immunoassay method kits.

Objective: Absolute and percentage CD4+ T-lymphocytes counts are useful in monitoring people living with HIV. In spite of point-of-care development, CD4 testing in some laboratories of resources-limited countries still use flow cytometers from many manufacturers. We evaluated three flow cytometers (FACSCOUNT CD4/CD4%, GUAVA Auto CD4/CD4%, CYFLOW Counter® CD4/CD4%) and brought out choice criteria according to laboratory resources. Methods: CD4 percent and absolute count obtained with 180 HIV-infected patients (adults and children) with evaluated platforms (FACSCOUNT CD4/CD4%, GUAVA Auto CD4/CD4%, CYFLOW Counter CD4/CD4%) were compared with those provided by FACSCalibur TruCount®. Agreement was analyzed using Bland-Altman analysis. We also carried out a Comparative analysis of technical and operational characteristics to identify strengths and weaknesses of each tested cytometer. Results: The median CD4 percentage and absolute count obtained with FACSCOUNT and CYFLOW were similar to those of FACSCALIBUR. By contrast, GUAVA showed higher values. Bland-Altman analysis did not show measurement error. However, GUAVA and CYFLOW gave a relative high bias with mean difference respectively -69 and +27CD4 cells/μl. The overall bias of CD4 percentage were >5% for the evaluated cytometers. There was a good interclass agreement (Kappa ≥ 0.78) and good measurement precision (coefficient of variation

Background The number of people who use drugs (PWUD) has dramatically increased in West Africa over the last 15 years, but targeted interventions are falling behind, notably because of the lack of awareness of the health needs of PWUD. We aimed to assess prevalence and factors associated with HIV and other infections in PWUD in Abidjan, Ivory Coast, one of the countries most affected by HIV in Western Africa. Methods We used respondent-driven-sampling to obtain a representative sample of heroin or cocaine/crack users aged 18 years or more. Socio-behavioral data were obtained by face-to-face questionnaires. Blood samples were collected and tested for HIV. Two sputa were obtained in tuberculosis (TB) symptomatic participants for acid-fast-bacilli (AFB) smear testing. After a descriptive analysis, crude prevalence were calculated, then weighted to take account of the sampling method. Factors associated with HIV and TB were studied using adjusted log-binomial regression. Population size was estimated by capture–recapture. Results 450 PWUD were recruited in May 2014. The mean age was 33.5 years; 10.9% were women. Smoking was the main mode of consumption, ever injecting was reported by 12.7% of the participants (3.6% in the past month). Sex work was reported by 15.8% of the PWUD (13.7% of the men), and 10.2% of the men reported sexual relationships with other men (MSM). We found a weighted prevalence of 9.5% for HIV. Women were 3.4 times more likely to be infected than men. Among men, being a sex worker (SW) (adjusted OR 2.9 [95CI 1.06–7.98]) or MSM (adjusted OR 11.5 [95CI 4.22–31.42]) were the main factors associated with HIV infection in adjusted analysis. Injection was not associated with HIV. TB weighted prevalence was 1.8%, associated with poor living arrangements in adjusted analysis. We estimated that 3521; 95CI 3049–3993 PWUD live in Abidjan. Conclusion PWUD in Abidjan are at high risk of HIV due to sexual transmission, especially in women, SW and MSM who also use drugs. Interventions should be developed to improve HIV prevention and linkage to care in these specific populations. More generally, improving the health of PWUD involves a broader reflection on the living environment and access to health care of slum residents in large African cities.

Objective: To assess the performance of QuantiFERON-TB Gold In-Tube (QFT-GIT) test for active tuberculosis (TB) in HIV adults, and its variation over time in patients on antiretroviral therapy (ART) and/or isoniazide preventive therapy (IPT). Methods: Transversal study and cohort nested in the Temprano ANRS 12136 randomized controlled trial assessing benefits of initiating ART earlier than currently recommended by World Health Organization, with or without a 6-month IPT. Performance of QFT-GIT for detecting active TB at baseline in the first 50% participants, and 12-month incidence of conversion/reversion in the first 25% participants were assessed. QFT-GIT threshold for positivity was 0.35 IU/ml. Results: Among the 975 first participants (median baseline CD4 count 383/mm 3 , positive QFT-GIT test 35%), 2.7% had active TB at baseline. QFT-GIT sensitivity, specificity, positive and negative predictive value for active TB were 88.0%, 66.6%, 6.5% and 99.5%. For the 444 patients with a second test at 12 months, rates for conversion and reversion were 9.3% and 14%. Reversion was more frequent in patients without ART and younger patients. IPT and early ART were not associated with reversion/conversion. Conclusion: A negative QFT-GIT could rule out active TB in HIV-infected adults not severely immunosuppressed, thus avoiding repeated TB testing and accelerating diagnosis and care for other diseases. Trial Registration: ClinicalTrials.gov NCT00495651.