Evaluation of the Diagnostic Performances of the SD-Bioline®HBeAg Rapid Test Used Routinely for the Management of HBV-Infected Individuals in Burkina Faso.

Hepatitis B e antigen (HBeAg) is a marker of wild-type hepatitis B virus replication. In resource-limited countries where access to enzyme-linked immunosorbent assay (ELISA) remains a challenge, rapid diagnostic tests (RDT) constitute a good alternative. The HBeAg status is employed to evaluate eligibility for antiviral therapy and to prevent the transmission of hepatitis B from mother to child (PMTCT). The objective of this study was to assess the diagnostic performance of the SD-Bioline®HBeAg RDT commonly used for detecting HBeAg in laboratories in Burkina Faso. The sample panel used was collected from HBsAg-positive patients received in the laboratory for the detection of HBeAg with the rapid test. The samples were retested for HBeAg using the VIDAS HBe/Anti-HBe enzyme-linked fluorescent assay (ELFA) (Gold standard). Then, the viral load (VL) of HBV DNA was determined using the GENERIC HBV CHARGE VIRLAE kit (GHBV-CV). The diagnostic performances of the SD-Bioline®HBeAg and its agreement with the gold standard were calculated with their 95% confidence intervals. Overall, 340 sera obtained from HBsAg-positive patients were included in this evaluation Compared to the VIDAS HBe/Anti-HBe ELFA test, the sensitivity (Se) and specificity (Sp) of the SD-Bioline®HBeAg test were 33.3% and 97.9%, respectively. The concordance between the two tests was 0.42. Depending on the viral load, the Se and Sp varied from 8.8% and 98.3% for a VL < 2000 IU/mL to 35.5% and 98.4% for a VL > 2,000,000 IU/mL. The results showed a low sensibility of the SD-Bioline®HBeAg RDT test, indicating that its use is inappropriate for the clinical management of HBV-infected patients. They also highlight the urgent need to develop HBeAg rapid tests with better sensitivities.

Residual risk of hepatitis B virus transmission through blood donations in Burkina Faso screened with rapid diagnostic tests.

Background and Aims: hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) represent the major transfusion-transmissible pathogens worldwide. The risk of transmission is relatively high in African countries, mainly due to unreliable screening methods of blood donations. In Burkina Faso, predonation screening using rapid diagnostic tests (RDTs) is widespread, raising the major question of the transfusion safety in the country. The objective of this study was to assess the risk of transmission of HBV, HCV, and HIV through blood transfusion in the context of the use of RDTs for screening of the blood donations. Methods: In this cross-sectional study, a total of 417 serum samples obtained from blood donors tested negative for HBsAg, anti-HCV, and anti-HIV using RDTs were retested for the same markers using chemiluminescent immunologic assays. Total antibodies to HBV core (anti-HBc) were tested on randomly selected samples. HBV-DNA and HCV-RNA viral loads (VLs) were quantified on HBsAg and anti-HCV positive samples, respectively. To assess possible occult hepatitis B infection (OBI), HBV-DNA-VL was quantified on 313 randomly selected HBsAg-negative samples. Results: HBsAg and anti-HCV were found respectively in 6 (6/417; 1.4%) and 11 (11/417; 2.6%) samples. No samples were reactive for anti-HIV. Total anti-HBc were detected in 217 out of the 319 randomly selected samples (217/319; 68.02%). HBV-DNA was detected in four (4/313; 1.27%) samples, including two (2/6; 33.33%) of the six HBsAg positive samples and two (2/313; 0.6%) of the HBsAg-negative samples, suggesting two cases of occult HBV infection. All anti-HCV antibody-positive samples were HCV-RNA negative. Conclusion: This study shows that RDTs are not sufficiently sensitive for the screening of blood donations. Our results highlight the urgent need to think about the extension of sensitive immunological tests in all blood transfusion centers and also the implementation of nucleic acid amplification techniques.

Analytical performance of eight rapid point-of-care tests routinely used for the detection of HBsAg in Burkina Faso: A cross-sectional study.

BACKGROUND: In limited resources countries, HBsAg-rapid diagnostic test (RDT) represents a good alternative for the diagnosis of hepatitis B virus (HBV) infection. Due to many factors that can influence their analytical performances, an evaluation with local biological samples before using on a large scale is recommended. OBJECTIVES: The aims of the study were: (i) to evaluate the analytical performance of eight commercial RDTs used in Burkina Faso for the detection of HBsAg using serum from blood donors, and (ii) to propose an algorithm using these RDTs based on their analytical performance. STUDY DESIGN: 109 HBsAg-positive and 216 HBsAg-negative samples were included in this evaluation. A modified version of the World Health Organization (WHO) algorithm for the detection of HBsAg was used as the gold standard. A pairwise combination of RDTs performance was done to choose the best diagnostic algorithm. RESULTS: All RDTs presented an excellent specificity (Sp) (≥99.0 %) except Accucare HBsAg® test. Sensitivity (Se) ranged from 90.8 % (95 % CI: 87.9-93.7) for Rapid Signal™ HBsAg to 92.8 % (95 % CI: 90.3-95.5) for SD BioLine® HBsAg and Artron® HBsAg. The pairwise combinations of the Se and Sp of RDTs showed no improvement in diagnostic performance. CONCLUSION: The RDTs evaluated in this study have good sensitivities and excellent specificities indicating their use in clinical practice and for HBV mass screening in Burkina Faso. However, their use should be monitored in the context of blood transfusion. Furthermore, according to our algorithm, each positive sample should be confirmed by another RDT of good Se.

Prevalence of Hepatitis B virus and Hepatitis D virus Coinfection in Western Burkina Faso and molecular characterization of the detected virus strains.

OBJECTIVES: In this study, we monitored the seroprevalence of HBV-HDV co-infection in different population groups in the Western part of Burkina Faso, and described the genetic diversity of the detected virus strains. METHODS: Between October 2013 and December 2014, venous blood samples were collected from different cohorts (blood donors, pregnant women, outpatients) in the western region of Burkina Faso. Samples were tested for HBsAg and total anti-HDV antibodies. Positive samples were further analysed for HBV-DNA and HDV-RNA. Genotyping of the detected virus strains was done by nucleotide sequencing and phylogenetic analyses. RESULTS: A total of 841 participants were included in this study. The mean age was 27.45 years (range: 7-89 years). HBsAg was found in 117 (13.9%) participants. Of the HBsAg positive samples, 4 (3.4%) were positive for total anti-HDV antibodies and negative for HDV RNA. Phylogenetic analyses based on the HBV complete genome (n=10) and S fragment sequences (n=35) showed that all strains belonged to genotype E. CONCLUSIONS: Our study showed a high HBsAg prevalence, but a low rate of HDV co-infection in HBsAg carriers from western Burkina Faso. The predominance of HBV genotype E in the country was confirmed. Our findings contribute to a better understanding of the burden of HBV and HDV infection in western Burkina Faso.

Epidemiology and molecular characterization of influenza viruses in Burkina Faso, sub-Saharan Africa.

BACKGROUND: The importance of influenza viruses in respiratory infections in sub-Saharan Africa has been historically overlooked, including in Burkina Faso. OBJECTIVES: This study therefore aimed at evaluating the prevalence and seasonal occurrence of influenza viruses in children under 5 years old, at risk of influenza-related complications, presenting with influenza-like illness (ILI) or severe acute respiratory infection (SARI). The study also aimed at identifying the periods with increased influenza transmission for vaccination recommendations in Burkina Faso. METHODS: From January 2014 to December 2015, ILI and SARI (2015 only) patients were recruited in six healthcare centers in Burkina Faso. Influenza A and B molecular detection and subtyping were performed. Clade clustering of a subset of A(H1N1)pdm09 and A(H3N2) strains was deduced by performing phylogenetic analyses on hemagglutinin gene sequences. Weekly surveillance data from FluNet (2011-2013; 2016) and this study (2014-2015) were used to identify periods of increased influenza activity. RESULTS: Influenza A and B viruses were detected in 15.1% (112 of 743) of ILI and 6.6% (12 of 181) of SARI patients. Overall, influenza A viruses were largely predominant (81 of 124, 65.3%), with 69.1% of A(H3N2) and 30.9% of A(H1N1)pdm09 strains. Four waves of increased transmission were identified in 2014-2015, each dominated by different influenza subtypes and clades. Between 2011 and 2016, periods of increased influenza activity varied in their frequency, duration, and timing. CONCLUSION: Influenza A and B viruses were detected in a substantial number of ILI and SARI cases in Burkina Faso. Vaccination in September-October would likely protect the highest number of patients.

Sentinel surveillance of influenza in Burkina Faso: identification of circulating strains during 2010-2012.

BACKGROUND: Although influenza surveillance has recently been improved in some sub-Saharan African countries, no information is yet available from Burkina Faso. OBJECTIVES: Our study was the first to determine the prevalence of influenza viruses circulating in Burkina Faso through a sentinel surveillance system. METHODS: We conducted sentinel surveillance with oropharyngeal (OP) swabs collected from outpatients (1 month to 83 years) from six sites in Bobo-Dioulasso and Ouagadougou, among patients meeting the WHO/CDC case definition for influenza-like illness (ILI; fever ≥38°C, and cough and/or sore throat in the absence of other diagnosis) from July 2010 to May 2012. Influenza viruses were detected by real-time RT-PCR using CDC primers, probes, and protocols. RESULTS: The first three ILI cases were enrolled each day; of 881 outpatients with ILI enrolled and sampled, 58 (6.6%) tested positive for influenza viruses (29 influenza A and 29 influenza B). Among the influenza A viruses, 55.2% (16/29) were influenza A (H1N1)pdm09 and 44.8% (13/29) were seasonal A (H3N2). No cases of seasonal A/H1N1 were detected. Patients within 0-5 years and 6-14 years were the most affected, comprising 41.4% and 22.4% laboratory-confirmed influenza cases, respectively. Influenza infections occurred during both the dry, dusty Harmattan months from November to March and the rainy season from June to October with peaks in January and August. CONCLUSIONS: This surveillance was the first confirming the circulation of influenza A (H1N1)pdm09, A/H3N2, and influenza B viruses in humans in Burkina Faso.