المؤلفون: Mahamat, Mahamat Hissene, Ségard, Adeline, Rayaisse, Jean-Baptiste, Argiles-Herrero, Rafael, Parker, Andrew Gordon, Solano, Philippe, Abd-Alla, Adly Mohamed Mohamed, Bouyer, Jérémy^{Aff4, Aff5}, Ravel, Sophie^{Aff2, IDs13071023057214_cor9}

المصدر: Parasites & Vectors. 16(1)

المؤلفون: Camara, Oumou, Camara, Mamadou, Falzon, Laura Cristina^{Aff2, Aff3}, Ilboudo, Hamidou, Kaboré, Jacques^{Aff5, Aff6}, Compaoré, Charlie Franck Alfred, Fèvre, Eric Maurice^{Aff2, Aff3}, Büscher, Philippe, Bucheton, Bruno^{Aff1, Aff8}, Lejon, Veerle^{Aff8, IDs40249023010761_cor10}

المصدر: Infectious Diseases of Poverty. 12(1)

المؤلفون: Juban Paola, Bart Jean-Mathieu, Ségard Adeline, Jamonneau Vincent, Ravel Sophie

المصدر: Parasite, Vol 31, p 15 (2024)

مصطلحات موضوعية: trypanosoma brucei gambiense, procyclic form, bloodstream form, glossina, life cycle, Infectious and parasitic diseases, RC109-216

الوصف: Trypanosoma brucei gambiense (Tbg) group 2 is a subgroup of trypanosomes able to infect humans and is found in West and Central Africa. Unlike other agents causing sleeping sickness, such as Tbg group 1 and Trypanosoma brucei rhodesiense, Tbg2 lacks the typical molecular markers associated with resistance to human serum. Only 36 strains of Tbg2 have been documented, and therefore, very limited research has been conducted despite their zoonotic nature. Some of these strains are only available in their procyclic form, which hinders human serum resistance assays and mechanistic studies. Furthermore, the understanding of Tbg2’s potential to infect tsetse flies and mammalian hosts is limited. In this study, 165 Glossina palpalis gambiensis flies were experimentally infected with procyclic Tbg2 parasites. It was found that 35 days post-infection, 43 flies out of the 80 still alive were found to be Tbg2 PCR-positive in the saliva. These flies were able to infect 3 out of the 4 mice used for blood-feeding. Dissection revealed that only six flies in fact carried mature infections in their midguts and salivary glands. Importantly, a single fly with a mature infection was sufficient to infect a mammalian host. This Tbg2 transmission success confirms that Tbg2 strains can establish in tsetse flies and infect mammalian hosts. This study describes an effective in vivo protocol for transforming Tbg2 from procyclic to bloodstream form, reproducing the complete Tbg2 cycle from G. p. gambiensis to mice. These findings provide valuable insights into Tbg2’s host infectivity, and will facilitate further research on mechanisms of human serum resistance.

وصف الملف: electronic resource

Relation: https://www.parasite-journal.org/articles/parasite/full_html/2024/01/parasite230155/parasite230155.html; https://doaj.org/toc/1776-1042

URL الوصول: https://doaj.org/article/522545f5a15046ab8e46ba0778ed6219

المؤلفون: Oumou Camara, Mamadou Camara, Laura Cristina Falzon, Hamidou Ilboudo, Jacques Kaboré, Charlie Franck Alfred Compaoré, Eric Maurice Fèvre, Philippe Büscher, Bruno Bucheton, Veerle Lejon

المصدر: Infectious Diseases of Poverty, Vol 12, Iss 1, Pp 1-14 (2023)

مصطلحات موضوعية: Human African trypanosomiasis, Trypanosoma brucei gambiense, Diagnosis, Clinical, Rapid diagnostic test, Sensitivity, Infectious and parasitic diseases, RC109-216, Public aspects of medicine, RA1-1270

الوصف: Abstract 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). Seropositives underwent parasitological examination (reference test) to confirm HAT and their DBS were tested in indirect enzyme-linked immunoassay (ELISA)/Trypanosoma brucei gambiense, trypanolysis, Loopamp Trypanosoma brucei Detection kit (LAMP) and m18S quantitative PCR (qPCR). Multivariable regression analysis assessed association of clinical presentation with HAT. Sensitivity, specificity, positive and negative predictive values of key clinical presentations, of the RDTs and of the DBS tests for HAT diagnosis were determined. Results The HAT prevalence, as confirmed parasitologically, was 2.0% (48/2345, 95% CI: 1.5–2.7%). Odds ratios (OR) for HAT were increased for participants with swollen lymph nodes (OR = 96.7, 95% CI: 20.7–452.0), important weight loss (OR = 20.4, 95% CI: 7.05–58.9), severe itching (OR = 45.9, 95% CI: 7.3–288.7) or motor disorders (OR = 4.5, 95% CI: 0.89–22.5). Presence of at least one of these clinical presentations was 75.6% (95% CI: 73.8–77.4%) specific and 97.9% (95% CI: 88.9–99.9%) sensitive for HAT. HAT Sero-K-Set, rHAT Sero-Strip, and SD Bioline HAT were respectively 97.5% (95% CI: 96.8–98.1%), 99.4% (95% CI: 99.0–99.7%) and 97.9% (95% CI: 97.2–98.4%) specific, and 100% (95% CI: 92.5–100.0%), 59.6% (95% CI: 44.3–73.3%) and 93.8% (95% CI: 82.8–98.7%) sensitive for HAT. The RDT’s positive and negative predictive values ranged from 45.2–66.7% and 99.2–100% respectively. All DBS tests had specificities ≥ 92.9%. While LAMP and m18S qPCR sensitivities were below 50%, trypanolysis and ELISA/T.b. gambiense had sensitivities of 85.3% (95% CI: 68.9–95.0%) and 67.6% (95% CI: 49.5–82.6%). Conclusions Presence of swollen lymph nodes, important weight loss, severe itching or motor disorders are simple but accurate clinical criteria for HAT referral in HAT endemic areas in Guinea. Diagnostic performances of HAT Sero-K-Set and SD Bioline HAT are sufficient for referring positives to microscopy. Trypanolysis on DBS may discriminate HAT patients from false RDT positives. Trial registration The trial was registered under NCT03356665 in clinicaltrials.gov (November 29, 2017, retrospectively registered https://clinicaltrials.gov/ct2/show/NCT03356665 ) Graphical Abstract

وصف الملف: electronic resource

Relation: https://doaj.org/toc/2049-9957

URL الوصول: https://doaj.org/article/e3afcc29ccba483d8f0d1dea0e0d417e

المؤلفون: Ipos Ngay Lukusa, Nick Van Reet, Dieudonné Mumba Ngoyi, Erick Mwamba Miaka, Justin Masumu, Pati Patient Pyana, Wilfried Mutombo, Digas Ngolo, Vincent Kobo, Felix Akwaso, Médard Ilunga, Lewis Kaninda, Sylvain Mutanda, Dieudonné Mpoyi Muamba, Olaf Valverde Mordt, Antoine Tarral, Sandra Rembry, Philippe Büscher, Veerle Lejon

المصدر: EBioMedicine, Vol 86, Iss , Pp 104376- (2022)

مصطلحات موضوعية: Human African trypanosomiasis, Trypanosoma brucei gambiense, Treatment outcome, Relapse, RNA, Diagnosis, Medicine, Medicine (General), R5-920

الوصف: Summary: Background: Detection of spliced leader (SL)-RNA allows sensitive diagnosis of gambiense human African trypanosomiasis (HAT). We investigated its diagnostic performance for treatment outcome assessment. Methods: Blood and cerebrospinal fluid (CSF) from a consecutive series of 97 HAT patients, originating from the Democratic Republic of the Congo, were prospectively collected before treatment with acoziborole, and during 18 months of longitudinal follow-up after treatment. For treatment outcome assessment, SL-RNA detection was compared with microscopic trypanosome detection and CSF white blood cell count. The trial was registered under NCT03112655 in clinicaltrials.gov. Findings: Before treatment, respectively 94.9% (92/97; CI 88.5–97.8%) and 67.7% (65/96; CI 57.8–76.2%) HAT patients were SL-RNA positive in blood or CSF. During follow-up, one patient relapsed with trypanosomes observed at 18 months, and was SL-RNA positive in blood and CSF at 12 months, and CSF positive at 18 months. Among cured patients, one individual tested SL-RNA positive in blood at month 12 (Specificity 98.9%; 90/91; CI 94.0–99.8%) and 18 (Specificity 98.9%; 88/89; CI 93.9–99.8%). Interpretation: SL-RNA detection for HAT treatment outcome assessment shows ≥98.9% specificity in blood and 100% in CSF, and may detect relapses without lumbar puncture. Funding: The DiTECT-HAT project is part of the EDCTP2 programme, supported by Horizon 2020, the European Union Funding for Research and Innovation (grant number DRIA-2014-306-DiTECT-HAT).

وصف الملف: electronic resource

Relation: http://www.sciencedirect.com/science/article/pii/S2352396422005588; https://doaj.org/toc/2352-3964

URL الوصول: https://doaj.org/article/dd066076d06b4e58ab678a33a34d9502

لا يتم عرض هذه النتيجة على الضيوف.
تسجيل الدخول للوصول الكامل.

Reviewers: Lutje, Vittoria ¹, Seixas, Jorge ², Kennedy, Adrian ³, Lutje, Vittoria ¹

Document Information: Cochrane Database of Systematic Reviews. This document is a Academic Journal
Review first published in Issue 8, 2010.
Protocol first published in Issue 4, 2006.
This version first published online: 28 June 2013 in Issue 6, 2013.

Cochrane Source Information: This record should be cited as: Lutje, Vittoria, Seixas, Jorge, Kennedy, Adrian, Lutje, Vittoria. Chemotherapy for second‐stage Human African trypanosomiasis. (Protocol) Cochrane Database of Systematic Reviews 2013, Issue 6. Art. No.: CD006201. DOI: 10.1002/14651858.CD006201.pub3.

المؤلفون: Joël Vourchakbé, Arnol Auvaker Z. Tiofack, Mpoame Mbida, Gustave Simo

المصدر: Parasites & Vectors, Vol 13, Iss 1, Pp 1-12 (2020)

مصطلحات موضوعية: Human African trypanosomiasis, Donkeys, Horses, Trypanosomes, Trypanosoma brucei gambiense, Infectious and parasitic diseases, RC109-216

الوصف: Abstract Background Equine trypanosomiases are complex infectious diseases with overlapping clinical signs defined by their mode of transmission. Despite their economic impacts, these diseases have been neglected by the scientific community, the veterinary authorities and regulatory organizations. To fill the observed knowledge gap, we undertook the identification of different trypanosome species and subspecies naturally infecting horses and donkeys within the Chadian sleeping sickness focus. The objective of the study was to investigate the potential role of these domestic animals as reservoirs of the human-infective Trypanosoma brucei gambiense. Method Blood samples were collected from 155 donkeys and 131 horses in three human African trypanosomiasis (HAT) foci in Chad. Rapid diagnostic test (RDT) and capillary tube centrifugation (CTC) test were used to search for trypanosome infections. DNA was extracted from each blood sample and different trypanosome species and subspecies were identified with molecular tools. Results From 286 blood samples collected, 54 (18.9%) and 36 (12.6%) were positive for RDT and CTC, respectively. PCR revealed 101 (35.3%) animals with trypanosome infections. The Cohen’s kappa coefficient used to evaluate the concordance between the diagnostic methods were low; ranging from 0.09 ± 0.05 to 0.48 ± 0.07. Trypanosomes of the subgenus Trypanozoon were the most prevalent (29.4%), followed by T. congolense forest (11.5%), Trypanosoma congolense savannah (4.9%) and Trypanosoma vivax (4.5%). Two donkeys and one horse from the Maro HAT focus were found with T. b. gambiense infections. No significant differences were observed in the infection rates of different trypanosomes between animal species and HAT foci. Conclusions This study revealed several trypanosome species and subspecies in donkeys and horses, highlighting the existence of AAT in HAT foci in Chad. The identification of T. b. gambiense in donkeys and horses suggests considering these animals as potential reservoir for HAT in Chad. The presence of both human-infective and human non-infective trypanosomes species highlights the need for developing joint control strategies for HAT and AAT.

وصف الملف: electronic resource

Relation: http://link.springer.com/article/10.1186/s13071-020-04192-1; https://doaj.org/toc/1756-3305

URL الوصول: https://doaj.org/article/ae260692c7c84b319a4cd873cafe8600

المؤلفون: Paschal Ugochukwu Umeakuana, Wendy Gibson, Romanus Chukwuduruo Ezeokonkwo, Boniface Maduka Anene

المصدر: Parasites & Vectors, Vol 12, Iss 1, Pp 1-7 (2019)

مصطلحات موضوعية: Canine trypanosomosis, Trypanosoma brucei gambiense, Trypanosoma brucei brucei, Trypanosoma congolense, Nsukka, Nigeria, Infectious and parasitic diseases, RC109-216

الوصف: Abstract Background Animal trypanosomosis is endemic in Nigeria, while the human disease caused by Trypanosoma brucei gambiense is rarely reported nowadays after efforts to bring it under control in the 20th century. The University of Nigeria Veterinary Teaching Hospital (UNVTH) is a reference centre located within the Nsukka area and serves Enugu and neighboring states, Benue, Kogi, Anambra and Delta. Among dogs presented to the UNVTH with canine trypanosomosis, T. brucei is frequently reported as the causative agent. However, this is by morphological identification under the microscope, which does not allow distinction of human-infective (T. b. gambiense) and non-human-infective (T. b. brucei) subspecies. Here, we used subspecies-specific PCR tests to distinguish T. b. gambiense and T. b. brucei. Methods Blood samples were collected on FTA cards from 19 dogs presenting with clinical signs of trypanosomosis at the UNVTH from January 2017 to December 2018. All dogs had a patent parasitaemia. DNA was extracted from the FTA cards using Chelex 100 resin and used as template for PCR. Results All infections were initially identified as belonging to subgenus Trypanozoon using a generic PCR test based on the internal transcribed spacer 1 (ITS1) of the ribosomal RNA locus and a PCR test specific for the 177 bp satellite DNA of subgenus Trypanozoon. None of the samples were positive using a specific PCR test for T. evansi Type A kinetoplast DNA minicircles. Further PCR tests specific for T. b. gambiense based on the TgsGP and AnTat 11.17 genes revealed that two of the dogs harboured T. b. gambiense. In addition to trypanosomes of subgenus Trypanozoon, T. congolense savannah was identified in one dog using a species-specific PCR test for this taxon. Conclusions Nineteen dogs presenting with canine African trypanosomosis at UNVTH were infected with trypanosomes of the T. brucei group and in two cases the trypanosomes were further identified to subspecies T. b. gambiense using specific PCR tests. Thus T. b. gambiense is one of the parasites responsible for canine African trypanosomosis in the Nsukka area of Nigeria and represents a serious danger to human health.

وصف الملف: electronic resource

Relation: http://link.springer.com/article/10.1186/s13071-019-3680-8; https://doaj.org/toc/1756-3305

URL الوصول: https://doaj.org/article/289c010c3e2b4c208a8143992124e2d4

المؤلفون: Larson Boundenga, Illich Manfred Mombo, Mouinga-Ondeme Augustin, Ngoubangoye Barthélémy, Patrice Makouloutou Nzassi, Nancy D. Moukodoum, Virginie Rougeron, Franck Prugnolle

المصدر: Pathogens, Vol 11, Iss 9, p 992 (2022)

مصطلحات موضوعية: trypanosomes, diversity, prevalence, domestic animals, Trypanosoma brucei gambiense, Gabon, Medicine

الوصف: Human African Trypanosomiasis (HAT) is an infectious disease caused by protozoan parasites belonging to the Trypanosoma genus. In sub-Saharan Africa, there is a significant threat as many people are at risk of infection. Despite this, HAT is classified as a neglected tropical disease. Over the last few years, several studies have reported the existence of a wide diversity of trypanosome species circulating in African animals. Thus, domestic and wild animals could be reservoirs of potentially dangerous trypanosomes for human populations. However, very little is known about the role of domestic animals in maintaining the transmission cycle of human trypanosomes in central Africa, especially in Gabon, where serious cases of infection are recorded each year, sometimes leading to hospitalization or death of patients. Komo-Mondah, located within Estuaries (Gabonese province), stays the most active HAT disease focus in Gabon, with a mean of 20 cases per year. In this study, we evaluated the diversity and prevalence of trypanosomes circulating in domestic animals using the Polymerase Chain Reaction (PCR) technique. We found that 19.34% (53/274) of the domestic animals we studied were infected with trypanosomes. The infection rates varied among taxa, with 23.21% (13/56) of dogs, 16.10% (19/118) of goats, and 21.00% (21/100) of sheep infected. In addition, we have observed a global mixed rate of infections of 20.75% (11/53) among infected individuals. Molecular analyses revealed that at least six Trypanosome species circulate in domestic animals in Gabon (T. congolense, T. simiae, T. simiae Tsavo, T. theileri, T. vivax, T. brucei (including T. brucei brucei, and T. brucei gambiense)). In conclusion, our study showed that domestic animals constitute important potential reservoirs for trypanosome parasites, including T. brucei gambiense, which is responsible for HAT.

وصف الملف: electronic resource

Relation: https://www.mdpi.com/2076-0817/11/9/992; https://doaj.org/toc/2076-0817

URL الوصول: https://doaj.org/article/cf9a5c8e6db941d79e1186927aa47083