Publications by authors named "Bucheton B"

Article Synopsis
  • The study investigates the presence of African trypanosomes in the skin of individuals at risk for gambiense Human African Trypanosomiasis (gHAT) in Guinea, finding that a significant number of seropositive individuals carry the parasites in their dermal layers.
  • Out of nearly 19,000 screened participants, 96 were included, revealing dermatological symptoms to be more common in seropositive individuals compared to seronegative ones.
  • Follow-up showed a decrease in skin parasite detection post-treatment, but a notable percentage of untreated seropositive individuals continued to test positive, highlighting potential challenges in achieving gHAT elimination.
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Background: Serological screening tests play a crucial role to diagnose gambiense human African trypanosomiasis (gHAT). Presently, they preselect individuals for microscopic confirmation, but in future "screen and treat" strategies they will identify individuals for treatment. Variability in reported specificities, the development of new rapid diagnostic tests (RDT) and the hypothesis that malaria infection may decrease RDT specificity led us to evaluate the specificity of 5 gHAT screening tests.

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Strategies 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.

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Article Synopsis
  • Trypanosoma brucei infects subcutaneous white adipose tissue, potentially aiding in its own transmission and contributing to weight loss in infected individuals.
  • The study reveals that T. brucei infection increases IL-17A-producing immune cells in adipose tissue, and a lack of IL-17 signaling protects against weight loss and fat wasting from the infection.
  • Additionally, without IL-17 signaling, preadipocytes accumulate and more parasites are found outside blood vessels in the adipose tissue, emphasizing the importance of IL-17 in managing immune responses and tissue dynamics during T. brucei infection.
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Human African Trypanosomiasis (HAT) is caused by which is transmitted by the tsetse fly insect vector ( spp). It is one of the 20 Neglected Tropical Diseases (NTD) listed by the WHO. These diseases affect the poorest and most vulnerable communities, for which the WHO has established a dedicated 2021-2030 roadmap.

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Background: Passive diagnosis of human African trypanosomiasis (HAT) at the health facility level is a major component of HAT control in Guinea. We examined which clinical signs and symptoms are associated with HAT, and assessed the performance of selected clinical presentations, of rapid diagnostic tests (RDT), and of reference laboratory tests on dried blood spots (DBS) for diagnosing HAT in Guinea.

Method: The study took place in 14 health facilities in Guinea, where 2345 clinical suspects were tested with RDTs (HAT Sero-K-Set, rHAT Sero-Strip, and SD Bioline HAT).

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Eliminating schistosomiasis as a public health problem by 2030 requires a better understanding of the disease transmission, especially the asymmetric distribution of worm burden in individuals living and sharing the same environment. It is in this light that this study was designed to identify human genetic determinants associated with high burden of S. mansoni and also with the plasma concentrations of IgE and four cytokines in children from two schistosomiasis endemic areas of Cameroon.

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In the context of the human African trypanosomiasis elimination process, reliable and accurate diagnostic tools are crucial for exploring the role of a potential animal reservoir of Trypanosoma brucei gambiense. The immune trypanolysis test (TL) using the variant antigen types (VAT) LiTat 1.3 and LiTat 1.

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After intensive control efforts, human African trypanosomiasis (HAT) was declared eliminated in Côte d'Ivoire as a public health problem in December 2020 and the current objective is to achieve the interruption of the transmission (zero cases). Reaching this objective could be hindered by the existence of an animal reservoir of Trypanosoma (T.) brucei (b.

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Approximately 25% of the risk of is associated with host genetic variation. We will test 24 candidate genes, mainly in the T 2 and T 17 pathways, for association with infection intensity in four African countries, using family based and case-control approaches. Children aged 5-15 years will be recruited in endemic areas of Ivory Coast, Cameroon, Uganda and the Democratic Republic of Congo (DRC).

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Background: Activities to control human African trypanosomiasis (HAT) in Guinea were severely hampered by the Ebola epidemic that hit this country between 2014 and 2016. Active screening was completely interrupted and passive screening could only be maintained in a few health facilities. At the end of the epidemic, medical interventions were progressively intensified to mitigate the risk of HAT resurgence and progress towards disease elimination.

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The objective set by WHO to reach elimination of human African trypanosomiasis (HAT) as a public health problem by 2020 is being achieved. The next target is the interruption of gambiense-HAT transmission in humans by 2030. To monitor progress towards this target, in areas where specialized local HAT control capacities will disappear, is a major challenge.

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Human African trypanosomiasis (HAT) is a protozoal disease transmitted by tsetse flies. Infection with trypanosomes can lead directly to active HAT or latent infection with no detectable parasites, which may progress to active HAT or to spontaneous self-cure. Genetic variation could explain these differences in the outcome of infection.

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Background: Significant efforts to control human African trypanosomiasis (HAT) over the two past decades have resulted in drastic decrease of its prevalence in Côte d'Ivoire. In this context, passive surveillance, integrated in the national health system and based on clinical suspicion, was reinforced. We describe here the health-seeking pathway of a girl who was the first HAT patient diagnosed through this strategy in August 2017.

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Africa contains more human genetic variation than any other continent, but the majority of the population-scale analyses of the African peoples have focused on just two of the four major linguistic groups, the Niger-Congo and Afro-Asiatic, leaving the Nilo-Saharan and Khoisan populations under-represented. In order to assess genetic variation and signatures of selection within a Nilo-Saharan population and between the Nilo-Saharan and Niger-Congo and Afro-Asiatic, we sequenced 50 genomes from the Nilo-Saharan Lugbara population of North-West Uganda and 250 genomes from 6 previously unsequenced Niger-Congo populations. We compared these data to data from a further 16 Eurasian and African populations including the Gumuz, another putative Nilo-Saharan population from Ethiopia.

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Background: The diagnosis of gambiense human African trypanosomiasis (gHAT) typically involves 2 steps: a serological screen, followed by the detection of living trypanosome parasites in the blood or lymph node aspirate. Live parasites can, however, remain undetected in some seropositive individuals, who, we hypothesize, are infected with Trypanosoma brucei gambiense parasites in their extravascular dermis.

Methods: To test this hypothesis, we conducted a prospective observational cohort study in the gHAT focus of Forecariah, Republic of Guinea.

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Article Synopsis
  • Copy number variation (CNV) is a significant form of genomic change affecting 75% of the human genome but is underreported in African populations, which could impact disease susceptibility and adaptation.
  • Researchers sequenced genomes from 232 individuals across three African ethno-linguistic groups, identifying 7608 CNVRs, including novel variants, and found that many were population-specific.
  • The study established a connection between CNVs and genetic selection, showing that CNVs were often linked to SNPs associated with conditions like HIV and preeclampsia, enhancing the understanding of African genomic diversity.
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Progress has been made in the control or elimination of tropical diseases, with a significant reduction of incidence. However, there is a risk of re-emergence if the factors fueling transmission are not dealt with. Although it is essential to understand these underlying factors for each disease, asymptomatic carriers are a common element that may promote resurgence; their impact in terms of proportion in the population and role in transmission needs to be determined.

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The World Health Organization (WHO) has set the goal of gambiense-Human African trypanosomiasis (HAT) elimination as a public health problem for 2020 and interruption of transmission in humans for 2030. In this context, it is crucial to monitor progress towards these targets using accurate tools to assess the level of transmission in a given area. The aim of this study was to investigate the relevance of the immune trypanolysis test (TL) as a population-based bioassay to evaluate Trypanosoma brucei gambiense transmission in various epidemiological contexts.

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In 2017, 1447 new cases of Human African Trypanosomiasis (HAT) were reported, which reflects considerable progress towards the World Health Organisation's target of eliminating HAT as a public health problem by 2020. However, current epidemiological data are still lacking for a number of areas, including historical HAT foci. In order to update the HAT situation in the historical focus of forested Guinea, we implemented a geographically based methodology: Identification of Villages at Risk (IVR).

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Trypanosoma brucei (T.b.) rhodesiense is the cause of the acute form of human African trypanosomiasis (HAT) in eastern and southern African countries.

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Infection by Trypanosoma brucei gambiense is characterized by a wide array of clinical outcomes, ranging from asymptomatic to acute disease and even spontaneous cure. In this study, we investigated the association between macrophage migrating inhibitory factor (MIF), an important pro-inflammatory cytokine that plays a central role in both innate and acquired immunity, and disease outcome during T. b.

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Article Synopsis
  • Human African trypanosomiasis (HAT), also known as sleeping sickness, is a serious neglected tropical disease caused by two species of the Trypanosoma parasite, with targets set by WHO for elimination by 2020 and zero transmission by 2030.
  • Diagnosis of HAT involves a complex process including clinical assessment, confirmation through antibody screening, and critical parasitological testing, as conventional methods often lack sensitivity and may not effectively detect low parasite levels.
  • The landmark technique developed by Sheila Lanham using anion exchange chromatography allows for efficient separation and identification of trypanosomes from blood, improving diagnostic accuracy and facilitating widespread screening through the Card Agglutination Test for Trypanosomiasis (CATT
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