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BackgroundTreatment of late-stage human African trypanosomiasis (HAT) with melarsoprol can be improved by shortening the regimen. A previous trial demonstrated the safety and efficacy of a 10-day treatment schedule. We demonstrate the effectiveness of this schedule in a noncontrolled, multinational drug-utilization study MethodsA total of 2020 patients with late-stage HAT were treated with the 10-day melarsoprol schedule in 16 centers in 7 African countries. We assessed outcome on the basis of major adverse events and the cure rate after treatment and during 2 years of follow-up ResultsThe cure rate 24 h after treatment was 93.9%; 2 years later, it was 86.2%. However, 49.3% of patients were lost to follow-up. The overall fatality rate was 5.9%. Of treated patients, 8.7% had an encephalopathic syndrome that was fatal 45.5% of the time. The rate of severe bullous and maculopapular eruptions was 0.8% and 6.8%, respectively ConclusionsThe 10-day treatment schedule was well implemented in the field and was effective. It reduces treatment duration, drug amount, and hospitalization costs per patient, and it increases treatment-center capacity. The shorter protocol has been recommended by the International Scientific Council for Trypanosomiasis Research and Control for the treatment of late-stage HAT caused by Trypanosoma brucei gambiense

Background Starting in 2008, the Central African Republic (CAR) experienced an unprecedented number of reported yellow fever (YF) cases. A risk assessment of YF virus (YFV) activity was conducted to estimate potential disease risk and vaccine needs. Methods A multistage cluster sampling design was used to sample humans, non-human primates, and mosquitoes in distinct ecologic zones. Humans and non-human primates were tested for YFV-specific antibodies; mosquitoes were tested for YFV RNA. Results Overall, 13.3% (125/938) of humans were found to have naturally-acquired YFV antibodies. Antibody levels were higher in zones in the southern and south central regions of CAR. All sampled non-human primates (n=56) were known YFV reservoirs; one tested positive for YFV antibodies. Several known YF vectors were identified including Aedes africanus, Ae. aegypti, Ae. luteocephalus, and Ae. simpsoni. Several more urban locations were found to have elevated Breateau and Container indices for Ae. aegypti. Conclusions A country-wide assessment of YF risk found YFV to be endemic in CAR. The potential for future YF cases and outbreaks, however, varied by ecologic zone. Improved vaccination coverage through mass campaign and childhood immunization was recommended to mitigate the YF risk.

Summary Methods Mosquito aquatic stages were collected in domestic and peri-domestic areas, and epidemic risk indexes (Breteau, Container) were calculated for each prospected location. Adult female mosquitoes were captured by human landing catches, while larvae were sampled by inspecting artificial and natural breeding sites in randomly selected premises. Results Seventy-eight adults Aedes albopictus were collected in Bangui and Bayanga. Mosquito biting rate and abundance were, respectively, 0.33–1.70 bites/human/hour and 14.6% in Bangui and 0.04–0.16 and 0.4% in Bayanga. Larval sampling revealed a large diversity of water container harbouring the species in Bangui, Bayanga, Nola and Salo including unused containers, old tires, vehicle carcasses, buckets, barrels and stem of bamboo. The epidemic risk indices were erratic according to the location, ranging between 1.5–27.6 for Breteau and 1.3–47.1 for Container. Conclusion This is the first record of Ae. albopictus in two bioclimatic zones of CAR This observation emphasizes the need to further investigate its potential impact on dengue and chikungunya viruses transmission regarding their recent emergences in Africa (Cote d’Ivoire, Senegal, Mali, Somalia, Gabon, Cape Verde Islands). Premier report de Aedes albopictus (Skuse 1894), en Republique centrafricaine Objectif: Publier le premier report de Ae. albopictus dans les 2 zones bioclimatiques de la Republique centrafricaine (RCA). Methodes: Des populations de moustiques ont eteechantillonnees dans 4 zones bioclimatiques afin d’evaluer le risque de fievre jaune. Les stades aquatiques des moustiques ont ete recueillis dans des zones domestiques et peri-domestiques et les indices de risque d’epidemie (Breteau, conteneurs) ont ete calcules pour chaque endroit prospecte. Des moustiques femelles adultes ont ete captures lors de leur descente sur l’homme alors que les larves ont eteechantillonnees en inspectant des sites artificiels et naturels de reproduction dans des locaux selectionnes de maniere aleatoire. Resultats: 78 adultes Ae. albopictus ont ete recueillis a Bangui et Bayanga. Le taux de piqures des moustiques et leur abondance etaient respectivement de 0,33 a 1,70 piqures/homme/heure et de 14,6%a Bangui et 0,04 a 0,16 piqures/homme/heure et 0,4%a Bayanga. L’echantillonnage des larves a revele une grande diversite des conteneurs d’eau abritant les especes a Bangui, Bayanga, Nola et Salo, tels que de vieux pneus, des carcasses de vehicules, des seaux, des tonneaux et des tiges de bambou. Les indices de risque d’epidemie variaient selon les sites, avec des indices Breteau allant de 1,5 a 27,6 et des indices conteneurs de 1,3 a 47,1. Conclusion: Ce premier report de Ae. albopictus dans les 2 zones bioclimatiques de la RCA met l’accent sur la necessite de continuer a investiguer son impact potentiel sur la dengue et la transmission du virus chikungunya en Cote d’Ivoire, au Senegal, au Mali, en Somalie, au Gabon, dans les iles du Cap Vert. Primer registro de Ae. albopictus (Skuse 1894), en la Republica Central Africana Objetivo: Reportar el primer registro de Aedes albopictus en 2 zonas bioclimaticas de la Republica Central Africana. Metodos: Se muestrearon poblaciones de mosquitos en 4 zonas bioclimaticas para evaluar el riesgo de fiebre amarilla. Se recolectaron estadios acuaticos del mosquito en areas domesticas y peridomesticas y se calcularon los indices de riesgo (Breteau, Contenedores) para cada localidad. Las hembras adultas del mosquito se capturaron mediante cebos humanos, mientras que las larvas se muestrearon inspeccionando lugares de reproduccion, tanto artificiales como naturales, en predios seleccionados al azar. Resultados: Se recolectaron 78 adultos de Ae. albopictus en Bangui y Bayanga. La tasa de picadura del mosquito y su abundancia fueron respectivamente 0.33-1.70 picaduras/humano/hora y 14.6% en Bangui y 0.04- 0.16 y 0.4% en Bayanga. El muestreo de larvas demostro la presencia de esta especie en una gran diversidad de contenedores de agua, tales como ruedas viejas, carcasas de vehiculos, cubos, barriles y canas de bamboo, en Bangui, Bayanga, Nola y Salo. Los indices de riesgo epidemico variaban entre lugares, estando entre 1.5 y 27.6 para Breteau y 1.3 a 47.1 para Contenedores. Conclusion: Este primer registro de Ae. albopictus en 2 zonas bioclimaticas de la Republica Central Africana subraya la necesidad de investigar mas a fondo su impacto potencial sobre la transmision del dengue y del virus de chikungunya en Costa de Marfil, Senegal, Mali, Somalia, Gabon, y las Islas de Cabo Verde.

Background. Treatment of late-stage human African trypanosomiasis (HAT) with melarsoprol can be improved by shortening the regimen. A previous trial demonstrated the safety and efficacy of a 10-day treatment schedule. We demonstrate the effectiveness of this schedule in a noncontrolled, multinational drug-utilization study. Methods. A total of 2020 patients with late-stage HAT were treated with the 10-day melarsoprol schedule in 16 centers in 7 African countries. We assessed outcome on the basis of major adverse events and the cure rate after treatment and during 2 years of follow-up. Results. The cure rate 24 h after treatment was 93.9%; 2 years later, it was 86.2%. However, 49.3% of patients were lost to follow-up. The overall fatality rate was 5.9%. Of treated patients, 8.7% had an encephalopathic syndrome that was fatal 45.5% of the time. The rate of severe bullous and maculopapular eruptions was 0.8% and 6.8%, respectively. Conclusions. The 10-day treatment schedule was well implemented in the field and was effective. It reduces treatment duration, drug amount, and hospitalization costs per patient, and it increases treatment-center capacity. The shorter protocol has been recommended by the International Scientific Council for Trypanosomiasis Research and Control for the treatment of late-stage HAT caused by Trypanosoma brucei gambiense.

Background The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV) represents a risk for spread of the disease, we undertook entomological investigations at these sites to identify potential vectors of YFV and their abundance. Findings Between 2006 and 2010, 5066 mosquitoes belonging to six genera and 43 species were identified. The 20 species of the Aedes genus identified included Ae. aegypti, the main vector of YFV in urban settings, and species found in tropical forests, such as Ae. africanus, Ae. simpsoni, Ae. luteocephalus, Ae. vittatus and Ae. opok. These species were not distributed uniformly in the various sites studied. Thus, the predominant Aedes species was Ae. aegypti in Bangui (90.7 %) and Basse-Kotto (42.2 %), Ae. africanus in Ombella-Mpoko (67.4 %) and Haute-Kotto (77.8 %) and Ae. vittatus in Ouham-Pende (62.2 %). Ae. albopictus was also found in Bangui. The distribution of these dominant species differed significantly according to study site (P Aedes mosquitoes analysed by polymerase chain reaction contained the YFV genome. Conclusion The results indicate a wide diversity of vector species for YFV in the Central African Republic. The establishment of surveillance and vector control programs should take into account the ecological specificity of each species.

International audience

Human African trypanosomiasis (HAT) or sleeping sickness is a disease characterized by a hemolymphatic stage 1 followed by a meningoencephalitic stage 2 which is fatal without specific treatment. Furthermore, due to the toxicity of drugs used to treat stage 2 (mainly melarsoprol) accurate staging is required. Actual criteria employed during field surveys are not sensitive enough for precise staging. Antineurofilament (anti-NF) and antigalactocerebrosides (anti-GalC) antibodies have been identified in cerebrospinal fluid (CSF) as potential markers of central nervous system (CNS) involvement. We describe a dot enzyme-linked immunosorbent assay (dot-ELISA) to detect anti-GalC and anti-NF antibodies and its value in staging. NF- and GalC-dotted nitrocellulose strips were first developed in our laboratory. They were then evaluated in Angola and Central African Republic on 140 CSF samples. Compared to our staging criteria (i.e., CSF cell count ≥ 20 cells/μl, CSF immunoglobulin M concentration ≥ 100 mg/liter, and/or the presence of trypanosomes in the CSF), combined detection of both CSF anti-NF and CSF anti-GalC by dot-ELISA showed 83.2% sensitivity and 100.0% specificity. Dot-ELISA could be a useful test to diagnose CNS involvement in HAT in the less-equipped laboratories or in the field situation and to improve patient treatment.

International audience

An outbreak of human African trypanosiaisis is ongoing in the High Mbomou area of the Central African Republic. This area is located on the Sudanese border approximately 1,100 kilometers from the capital city of Bangui. According to current estimates, the cost of implementing the National Human African Trypanosomiasis Program is 754,000 United States Dollars, i.e., 4.1 dollars per protected inhabitant. However actual conditions in the field suggest that this estimate should be revised. Special field conditions include constant refugee movement across the border, lack of accurate epidemiological data concerning neighboring Haut Zaire, and low participation of village residents in mass screening operations (less than 50%). In response to these problems, the authors recommend the organization of more exploratory missions to allow better targeting of screening and therapy. In the initial plan, exploratory missions were to account for 1% of the total cost. This proportion will probably require upward adjustment.

OBJECTIVE: To evaluate the performance of serological tests using dried blood on filter-papers (micro-card agglutination test for trypanosomiasis (micro-CATT)) performed under field and laboratory conditions and using whole blood ((CATT/T.b. gambiense) (wb-CATT) and latex agglutination (LATEX/T.b. gambiense) (wb-LATEX)) for the serodiagnosis and surveillance of human African trypanosomiasis in West and Central Africa. METHODS: We evaluated the micro-CATT, wb-CATT and wb-LATEX methods in Côte d'Ivoire and the Central African Republic by screening 940 people. Sensitivity and specificity were calculated for each serological test; only patients with the confirmed presence of trypanosomes in the blood or lymph aspirate were considered true positives. Positive and negative predictive values were also calculated. FINDINGS: Each of the tests showed a lower sensitivity in the Central African Republic than in Côte d'Ivoire. CONCLUSION: The results confirmed the efficiency of the classic wb-CATT to detect sleeping sickness patients. The micro-CATT method can be used for human African trypanosomiasis surveillance if the test is performed on the same day as the blood collection, or if samples are stored at 4 degrees C. Otherwise, micro-CATT can be used when absolute sensitivity is not required. wb-LATEX should only be used for high-specificity screening.