Monitoring the elimination of gambiense human African trypanosomiasis in the historical focus of Batié, South-West Burkina Faso

The World Health Organisation has targeted the elimination of human African trypanosomiasis (HAT) as zero transmission by 2030. Continued surveillance needs to be in place for early detection of re-emergent cases. In this context, the performance of diagnostic tests and testing algorithms for detection of the re-emergence of Trypanosoma brucei gambiense HAT remains to be assessed. We carried out a door-to-door active medical survey for HAT in the historical focus of Batié, South-West Burkina Faso. Screening was done using three rapid diagnostic tests (RDTs). Two laboratory tests (ELISA/T. b. gambiense and immune trypanolysis) and parasitological examination were performed on RDT positives only. In total, 5883 participants were screened, among which 842 (14%) tested positive in at least one RDT. Blood from 519 RDT positives was examined microscopically but no trypanosomes were observed. The HAT Sero-K-Set test showed the lowest specificity of 89%, while the specificities of SD Bioline HAT and rHAT Sero-Strip were 92% and 99%, respectively. The specificity of ELISA/T. b. gambiense and trypanolysis was 99% (98-99%) and 100% (99-100%), respectively. Our results suggest that T. b. gambiense is no longer circulating in the study area and that zero transmission has probably been attained. While a least cost analysis is still required, our study showed that RDT preselection followed by trypanolysis may be a useful strategy for post-elimination surveillance in Burkina Faso.</p

Carbone des sols en Afrique

Les sols sont une ressource essentielle à préserver pour la production d’aliments, de fibres, de biomasse, pour la filtration de l’eau, la préservation de la biodiversité et le stockage du carbone. En tant que réservoirs de carbone, les sols sont par ailleurs appelés à jouer un rôle primordial dans la lutte contre l’augmentation de la concentration de gaz à effet de serre. Ils sont ainsi au centre des objectifs de développement durable (ODD) des Nations unies, notamment les ODD 2 « Faim zéro », 13 « Lutte contre le changement climatique », 15 « Vie terrestre », 12 « Consommation et production responsables » ou encore 1 « Pas de pauvreté ». Cet ouvrage présente un état des lieux des sols africains dans toute leur diversité, mais au-delà, il documente les capacités de stockage de carbone selon les types de sols et leurs usages en Afrique. Il propose également des recommandations autour de l’acquisition et de l’interprétation des données, ainsi que des options pour préserver, voire augmenter les stocks de carbone dans les sols. Tous les chercheurs et acteurs du développement impliqués dans les recherches sur le rôle du carbone des sols sont concernés par cette synthèse collective. Fruit d’une collaboration entre chercheurs africains et européens, ce livre insiste sur la nécessité de prendre en compte la grande variété des contextes agricoles et forestiers africains pour améliorer nos connaissances sur les capacités de stockage de carbone des sols et lutter contre le changement climatique

C14- Evaluation de la qualité des disques d’Amoxicilline et d’Amoxicilline + Acide clavulanique utilisés au Burkina Faso

Introduction : Les disques d’antibiotiques utilisés dans les laboratoires d’analyses médicales proviennent de plusieurs fabricants et fournisseurs et doivent répondre à des exigences strictes de qualité. Cette étude a été entreprise pour évaluer la qualité des disques d’Amoxicilline et d’Amoxicilline + acide clavulanique utilisés au Burkina Faso. Matériel et méthodes : Une enquête sur l’utilisation des disques d’antibiotiques a été réalisée dans 20 laboratoires sites sentinelles de surveillance de la RAM. Des échantillons de disques d’Amoxicilline et d’Amoxicilline + acide clavulanique de quatre fabricants ont été collectés auprès de certains de ces laboratoires et de fournisseurs de disques d’antibiotiques. La qualité des disques d’Amoxicilline et des disques d’Amoxicilline + acide clavulanique a été évaluée en testant leur efficacité sur des souches d’Escherichia coli ATCC 25922 et Staphylococcus aureus ATCC 25923 et en dosant les antibiotiques par chromatographie liquide à haute performance. Résultats : Escherichia coli ATCC 25922 et Staphylococcus aureus ATCC 25923 étaient résistantes à 30,0 % pour les disques d’Amoxicilline + acide clavulanique et 55,6 % pour les disques d’Amoxicilline testés. Par ailleurs, les essais de dosage de l’amoxicilline ont révélé que 22,2% et 45,5% respectivement des disques d’Amoxicilline et des disques d’Amoxicilline + acide clavulanique contrôlés étaient conformes aux spécifications de l’OMS. Aucun échantillon ne contenait une teneur en Acide clavulanique conforme à la spécification. Conclusion : Cette étude révèle que la majorité des disques d’Amoxicilline et d’Amoxicilline + acide clavulanique contrôlés n’était pas conformes aux spécifications de qualité. Son extension à un nombre plus important d’antibiotiques permettra de mieux documenter la qualité des disques d’antibiotiques

PHYSICOCHEMICAL QUALITY AND LYODISPONIBILITY OF FIXED-DOSE ARTEMETHER-LUMEFANTRINE COMBINATIONS DISPENSED IN BURKINA FASO

peer reviewedThe purpose of this study was to evaluate the pharmaceutical quality and lyodisponibility of fixed-dose combinations of artemether-lumefantrinere found on the market in Burkina Faso. For this purpose, 122 samples were collected from dispensing sites in public and private health facilities and routine physico-chemical parameters were evaluated. Routine physicochemical parameters were evaluated. The in vitro comparative dissolution test was used to assess the lyodisponsibility of the samples in comparison to the originator drugs

Evaluation of the physicochemical quality and antimicrobial performance of amoxicillin and amoxicillin + clavulanic acid discs used in Burkina Faso

Antibiotic discs used in medical analysis laboratories are sourced from multiple manufacturers and suppliers and must meet stringent quality requirements. This study aimed to assess the quality and performance of amoxicillin and amoxicillin + clavulanic acid discs used in Burkina Faso. An evaluation of the use of antibiotic discs was initially conducted in the 20 sentinel laboratories for antimicrobial resistance surveillance in Burkina Faso. Then, various brands of amoxicillin and amoxicillin + clavulanic acid discs samples were collected from medical laboratories and local distributors. Quality control tests (identification and assay) were performed by high-performance liquid chromatography according to the validated method adapted from the USP monograph. The performance of the discs was assessed by testing their efficacy against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 strains. Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 were resistant to 30% of amoxicillin + clavulanic acid discs and to 55.6% of amoxicillin discs collected. In addition, only 22.2% and 45.5% of amoxicillin and amoxicillin + clavulanic acid discs tested met the specifications for amoxicillin contents. No brand of amoxicillin + clavulanic acid discs collected met the specifications for clavulanic acid content. Extending this study to a larger number of antibiotics would enable better documentation of the antibiotic disc quality.

Conducting active screening for human African trypanosomiasis with rapid diagnostic tests: The Guinean experience (2016–2021)

International audienceStrategies to detect Human African Trypanosomiasis (HAT) cases rely on serological screening of populations exposed to trypanosomes. In Guinea, mass medical screening surveys performed with the Card Agglutination Test for Trypanosomiasis have been progressively replaced by door-to-door approaches using Rapid Diagnostic Tests (RDTs) since 2016. However, RDTs availability represents a major concern and medical teams must often adapt, even in the absence of prior RDT performance evaluation. For the last 5 years, the Guinean HAT National Control Program had to combine three different RDTs according to their availability and price: the SD Bioline HAT (not available anymore), the HAT Sero-K-SeT (most expensive), and recently the Abbott Bioline HAT 2.0 (limited field evaluation). Here, we assess the performance of these RDTs, alone or in different combinations, through the analysis of both prospective and retrospective data. A parallel assessment showed a higher positivity rate of Abbott Bioline HAT 2.0 (6.0%, n = 2,250) as compared to HAT Sero-K-SeT (1.9%), with a combined positive predictive value (PPV) of 20.0%. However, an evaluation of Abbott Bioline HAT 2.0 alone revealed a low PPV of 3.9% (n = 6,930) which was surpassed when using Abbott Bioline HAT 2.0 in first line and HAT Sero-K-SeT as a secondary test before confirmation, with a combined PPV reaching 44.4%. A retrospective evaluation of all 3 RDTs was then conducted on 189 plasma samples from the HAT-NCP biobank, confirming the higher sensitivity (94.0% [85.6–97.7%]) and lower specificity (83.6% [76.0–89.1%]) of Abbott Bioline HAT 2.0 as compared to SD Bioline HAT (Se 64.2% [52.2–74.6%]—Sp 98.4% [94.2–99.5%]) and HAT Sero-K-SeT (Se 88.1% [78.2–93.8%]—Sp 98.4% [94.2–99.5%]). A comparison of Abbott Bioline HAT 2.0 and malaria-RDT positivity rates on 479 subjects living in HAT-free malaria-endemic areas further revealed that a significantly higher proportion of subjects positive in Abbott Bioline HAT 2.0 were also positive in malaria-RDT, suggesting a possible cross-reaction of Abbott Bioline HAT 2.0 with malaria-related biological factors in about 10% of malaria cases. This would explain, at least in part, the limited specificity of Abbott Bioline HAT 2.0. Overall, Abbott Bioline HAT 2.0 seems suitable as first line RDT in combination with a second HAT RDT to prevent confirmatory lab overload and loss of suspects during referral for confirmation. A state-of-the-art prospective comparative study is further required for comparing all current and future HAT RDTs to propose an optimal combination of RDTs for door-to-door active screening

Comparison of the sensitivity and specificity of HAT RDTs on frozen plasma samples from the HAT-NCP biobank (2017–2020) as compared to the initial parasitological diagnostic by mAECT and/or direct examination of lymph node aspirates.

Comparison of the sensitivity and specificity of HAT RDTs on frozen plasma samples from the HAT-NCP biobank (2017–2020) as compared to the initial parasitological diagnostic by mAECT and/or direct examination of lymph node aspirates.</p

Usage and performance of Abbott Bioline HAT 2.0 for D2D active screening in Guinea in 2021.

Usage and performance of Abbott Bioline HAT 2.0 for D2D active screening in Guinea in 2021.</p