The wing venation patterns to identify single tsetse flies.

This is the first study to explore the potential of various geometric morphometrics methods to help the morphological diagnostic of tsetse species, vectors of human and animal trypanosomiases in sub-Saharan Africa. We compared landmarks, semilandmarks and outlines techniques on male and female samples of species, and suggested adapted strategies according to the countries and their own Glossina fauna. We could compare up to 7 taxa belonging to the three main subgenera of the Glossina genus: Nemorhina (5 species), Glossina (1 species) and Austenina (1 species). Our sample included the major vectors of sleeping sickness: G. palpalis palpalis, G. p. gambiensis, G. fuscipes fuscipes and G. f. quanzensis, as well as two important vectors of African animal trypanosomoses: G. tachinoides and Glossina morsitans submorsitans. The average level of correct species recognition by the wing shape was satisfactory, and slightly higher for females than for males. The best scores of correct assignment, in both sexes, were obtained by the contour technique (96% of correct attribution in females, 92% in males), slightly higher than for semilandmarks (95% and 91%) or landmarks (94% and 89%) techniques. We made our images of wings freely available to be used as reference images (http://mome-clic.com), and we describe the conditions and the analytical steps to be followed to identify unknown specimens using external reference images. Under adequate conditions, such use of reference images obtained from a free access server could help species identification of new samples anywhere in Africa.

Variations in attack behaviours between Glossina palpalis gambiensis and G. tachinoides in a gallery forest suggest host specificity.

Tsetse flies Glossina palpalis gambiensis and G. tachinoides are among the major vectors of sleeping sickness (Human African Trypanosomiasis-HAT) and nagana (African Animal Trypanosomiasis - AAT) in West Africa. Both riparian species occur sympatrically in gallery forests of south west Burkina Faso, but little is known of their interspecies relationships although different authors think there may be some competition between them. The aim of this study was to check if sympatric species have different strategies when approaching a host. A man placed in a sticky cube (1 m × 1 m × 1 m) and a sticky black-blue-black target (1 m × 1 m) were used to capture tsetse along the Comoe river banks in a Latin Square design. The number and the height at which tsetse were caught by each capture method were recorded according to species and sex. Glossina p. gambiensis was more attracted to human bait than to the target, but both species were captured at a significantly higher height on the target compared with the human bait (P < 0.05). No significant difference in heights was found between G. tachinoides and G. p. gambiensis captured on targets (33 and 35 cm, respectively, P > 0.05). However, catches on human bait showed a significant difference in height between G. tachinoides and G. p. gambiensis (22.5 and 30.6 cm, respectively, P < 0.001). This study showed that these sympatric species had different attack behaviours to humans, which is not the case with the target. The implications of these findings are discussed.

[Therapeutic outcomes of anti-tuberculosis treatment in the context of HIV-tuberculosis co-infection: Cohort of Kabinda Center in Kinshasa, Democratic Republic of Congo]. / Issues thérapeutiques du traitement antituberculeux dans le contexte de la co-infection VIH-tuberculose : cohorte du centre de Kabinda à Kinshasa, République démocratique du Congo.

BACKGROUND: The study aimed to determine the clinical forms of tuberculosis and therapeutic outcome of anti-tuberculosis treatment in the context of HIV-tuberculosis co-infection. METHODS: A retrospective cohort of 120 HIV-positive patients with tuberculosis and 297 HIV-negative patients with tuberculosis attending the Kabinda Center was followed from 2010 to June, 30th 2013. The logistic regression model identified the determinants of a defavorable outcome after initiation of tuberculostatics. RESULTS: The proportion of female patients was higher in the co-infected group compared with the non-co-infected group (60.8% versus 42.7%, P<0.001). HIV-seropositive patients had more forms of pulmonary smear-negative (39.2% versus 25.3%, P<0.002) and extra-pulmonary (38% versus 35%, P<0.002) tuberculosis than HIV-negative patients. HIV-positive serology (OR: 3.13, 95%CI: 1.72-5.69) and age of patients more than 41 years (OR: 3.15, 95%CI: 1.36-7.29) were associated with an unfavorable outcome. CONCLUSION: This study highlights the usefulness of a systematically determining immunological status in co-infected patients and a timely and systematic ARV treatment, together with early diagnosis of tuberculosis. It also emphasizes the importance of adherence to support measures in order to improve tuberculosis treatment outcomes in co-infected patients.

Tsetse diversity and abundance in Southern Burkina Faso in relation with the vegetation.

The increase of human population, combined with climatic changes, contributed to the modification of spatial distribution of tsetse flies, main vector of trypanosomiasis. In order to establish and compare tsetse presence and their relationship with vegetation, entomological survey was performed using biconical traps deployed in transects, simultaneously with phyto-sociological study, on the Comoe river at its source in the village of Moussodougou, and in the semi-protected area of Folonzo, both localities in Southern Burkina Faso. In Folonzo, the survey revealed a diversity of tsetse with 4 species occurring with apparent densities as follows: Glossina tachinoides (8.9 tsetse/trap/day); G. morsitans submorsitans (1.8 tsetse/trap/day); G. palpalis gambiensis (0.6/trap/day) and G. medicorum (0.15 tsetse/trap/day). In Moussodougou, a highly anthropized area, mainly G. p. gambiensis was caught (2.06 tsetse/trap/day), and rarely G. tachinoides. The phyto-sociological study allowed discrimination of 6 types of vegetation in both localities, with 3 concordances that are riparian forest, shrubby and woody savannah. In Moussodougou, all tsetse were caught in the riparian forest. That was also the case in Folonzo where a great proportion (95 to 99 % following the season) of G. p. gambiensis and G. tachinoides were caught in the gallery, while G. m. submorsitans was occurring as well in the gallery as in the savannah, and G. medicorum in the forest gallery. This study showed that although G. tachinoides and G.p. gambiensis are both riparian, they do not have the same preference in terms of biotope.

Retina layer segmentation using kernel graph cuts and continuous max-flow.

Circular scan Spectral-Domain Optic Coherence Tomography imaging (SD-OCT) is one of the best tools for diagnosis of retinal diseases. This technique provides more comprehensive detail of the retinal morphology and layers around the optic disc nerve head (ONH). Since manual labelling of the retinal layers can be tedious and time consuming, accurate and robust automated segmentation methods are needed to provide the thickness evaluation of these layers in retinal disorder assessments such as glaucoma. The proposed method serves this purpose by performing the segmentation of retinal layers boundaries in circular SD-OCT scans acquired around the ONH. The layers are detected by adapting a graph cut segmentation technique that includes a kernel-induced space and a continuous multiplier based max-flow algorithm. Results from scan images acquired with Spectralis (Heidelberg Engineering, Germany) prove that the proposed method is robust and efficient in detecting the retinal layers boundaries in images. With a mean root-mean-square error (RMSE) of 0.0835 ± 0.0495 and an average Dice coefficient of 0.9468 ± 0.0705 pixels for the retinal nerve fibre layer thickness, the proposed method demonstrated effective agreement with manual annotations.

[Predictors of cesarean delivery in the Kinkanda general hospital in Matadi (Democratic Republic of Congo)]. / Les predicteurs de l'accouchement par cesarienne a l'hopital general de reference de Kinkanda a Matadi (Republique Democratique du Congo).

OBJECTIVE: To identify predictors of cesarean delivery in the Kinkanda general hospital. METHOD: Cross-sectional study conducted from 1st January 2012 to 31st December 2012, on women in labor who delivered at the maternity of Kinkanda. Predictors of cesarean delivery were identified by using binary logistic regression. RESULTS: A uterine height of at least 33 cm at induction of labor (AOR 3.93 95% CI 2.04 to 7.59; p <0.001), primiparity (AOR 2.1 95%CI:1.06 to 4.15; p = 0.033), non-membership of the pregnant woman to this particular health center area (AOR 4.26 95%CI 2.16 to 8.42; p <0.001) and a weight of the newborn of at least 4000g (AOR 7.8 95%CI 2.3 to 26.44; p <0.001) were identified as risk factors for cesarean delivery. CONCLUSION: Primiparity, uterine height of at least 33 cm, living in another health area than the Matadi area and fetal macrosomia are the main predictors of cesarean delivery during the year 2012 at the Kinkanda general hospital.

OBJECTIF: Identifier les prédicteurs de l'accouchement par césarienne à l'Hôpital Général de Kinkanda. MÉTHODE: Etude transversale analytique réalisée du 01 janvier au 31 décembre 2012, auprès de parturientes ayant accouché à la maternité de l'Hôpital Général de Kinkanda. Les variables prédictives de l'accouchement par césarienne ont été mises en évidence à l'aide d'une régression logistique binaire. RÉSULTATS: Une hauteur utérine d'au moins 33 cm au déclenchement du travail (ORA : 3,93 IC95% : 2,04 ­ 7,59 ; p < 0,001), la primiparité (ORA :2,1 IC95% :1,06 ­ 4,15 ; p= 0,033), la non appartenance de la parturiente à la zone de santé (ORA : 4,26 IC95% : 2,16 ­ 8,42 ; p < 0,001) et le poids du nouveau- né avec au moins 4000g (ORA : 7,8 IC95% : 2,3 ­ 26,44 ; p< 0,001) ont été identifiés comme des facteurs prédictifs de l'accouchement par césarienne. CONCLUSION: La primiparité, la hauteur utérine d'au moins 33 cm, l'appartenance à une autre zone de santé que celle de l'Hôpital Général de Kinkanda et la macrosomie fœtale sont les principaux prédicteurs de la césarienne au cours de l'année 2012 à l'Hôpital Général de Référence de Kinkanda.

Outline-based morphometrics, an overlooked method in arthropod studies?

Modern methods allow a geometric representation of forms, separating size and shape. In entomology, as well as in many other fields involving arthropod studies, shape variation has proved useful for species identification and population characterization. In medical entomology, it has been applied to very specific questions such as population structure, reinfestation of insecticide-treated areas and cryptic species recognition. For shape comparisons, great importance is given to the quality of landmarks in terms of comparability. Two conceptually and statistically separate approaches are: (i) landmark-based morphometrics, based on the relative position of a few anatomical "true" or "traditional" landmarks, and (ii) outline-based morphometrics, which captures the contour of forms through a sequence of close "pseudo-landmarks". Most of the studies on insects of medical, veterinary or economic importance make use of the landmark approach. The present survey makes a case for the outline method, here based on elliptic Fourier analysis. The collection of pseudo-landmarks may require the manual digitization of many points and, for this reason, might appear less attractive. It, however, has the ability to compare homologous organs or structures having no landmarks at all. This strength offers the possibility to study a wider range of anatomical structures and thus, a larger range of arthropods. We present a few examples highlighting its interest for separating close or cryptic species, or characterizing conspecific geographic populations, in a series of different vector organisms. In this simple application, i.e. the recognition of close or cryptic forms, the outline approach provided similar scores as those obtained by the landmark-based approach.

[Determinants of survival in HIV patients receiving antiretroviral therapy in Goma, Democratic Republic of Congo]. / Les déterminants de la survie des patients vivant avec le VIH sous thérapie antirétrovirale dans la ville de Goma, RD-Congo.

BACKGROUND: The study aimed to identify factors associated with the survival of patients receiving antiretroviral therapy. METHODS: A historic cohort of HIV patients from two major hospitals in Goma (Democratic Republic of Congo) was followed from 2004 to 2012. The Kaplan-Meier method was used to describe the probability of survival as a function of time since inclusion into the cohort. The log-rank test was used to compare survival curves based on determinants. The Cox regression model identified the determinants of survival since treatment induction. RESULTS: The median follow-up time was 3.56 years (IQR=2.22-5.39). The mortality rate was 40 deaths per 1000 person-years. Male gender (RR: 2.56; 95 %CI 1.66-4.83), advanced clinical stage (RR: 2.12; 95 %CI 1.15-3.90), low CD4 count (CD4 < 50) (RR: 2.05; 95 %CI : 1.22-3.45), anemia (RR: 3.95; 95 %CI 2.60-6.01), chemoprophylaxis with cotrimoxazole (RR: 4.29, 95 % CI 2.69-6.86) and period of treatment initiation (2010-2011) (RR: 3.34; 95 %CI 1.24-8.98) were statistically associated with short survival. CONCLUSION: Initiation of treatment at an early stage of the disease with use of less toxic molecules and an increased surveillance especially of male patients are recommended to reduce mortality.

[Human African trypanosomiasis in Côte d'Ivoire and Burkina Faso: optimization of epidemiologic surveillance strategies]. / La Trypanosomose Humaine Africaine dans l'espace ivoiro-burkinabé : optimisation des stratégies de surveillance épidémiologique.

The objective of this paper was to describe recent data from Burkina Faso and Côte d'Ivoire on Human African Trypanosomosis medical monitoring in order to (i) update the disease situation in these two countries that have been sharing important migratory, economic and epidemiological links for more than a century and (ii) to define the future strategic plans to achieve the goal of a sustainable control/elimination process. Results of active and passive surveillance indicate that all sleeping sickness patients diagnosed these last years in Burkina Faso were imported cases from Côte d'Ivoire. Nevertheless the re-introduction of the parasite is effective and the risk of a resumption of transmission exists. In Côte d'Ivoire, few cases are still diagnosed in several historical foci and the fear exists that the disease could reemerge in these foci or spread to other areas. In order to achieve a sustainable elimination of sleeping sickness in these two countries, control entities have to adapt their strategy to the different epidemiological contexts. At the exception of specific cases, the current disease prevalence no longer justifies the use of expensive medical surveys by exhaustive screening of the population. New disease control strategies, based on the exchange of epidemiological information between the two countries and integrated to the regular national health systems are required to target priority intervention areas. Follow-up in time of both treated patients and serological suspects that are potential asymptomatic carriers of parasite is also important. In parallel, researchers need to better characterize the respective roles of the human and animal reservoir in the maintenance of transmission and evaluate the different control strategies taken by National Control Programs in term of cost/effectiveness to help optimize them.

Déterminants de l'utilisation de la moustiquaire impregnée d'insecticide chez les enfants de moins de cinq ans à Kinshasa

Contexte. Le paludisme est un probleme majeur de sante publique en Republique Democratique du Congo. L'utilisation de la moustiquaire impregnee d'insecticide (MII) compte parmi les options les plus efficaces retenues pour lutter contre ce fleau. Cette pratique est encore faible dans la communaute et loin d'approcher le seuil de 60fixe par le sommet d'Abuja. Objectif. Identifier les determinants de l'utilisation de la MII par les enfants de moins de cinq ans a Kinshasa Materiel et methodes. Etude de type transversale; conduite entre le 05 et le 20 aout 2008; dans la zone de sante de Lemba a Kinshasa; sur un echantillon de 299 menages. L'unite statistique retenue dans l'etude etait le menage disposant d'au moins un enfant de moins de cinq ans. La prevalence de l'utilisation de la MII a ete estimee; et la regression logistique a permis d'en identifier les determinants. Resultats. La frequence d'utilisation de la MII dans la population d'etude etait de 42;5(IC95: 36;9 - 48;1). Les determinants de son utilisation identifies etaient : la taille du menage (p= 0;032); l'utilisation d'alternatives a la MII (OR : 0;27 ; IC95:0;15 - 0;48 ; p 0;001) ; l'exposition aux p

[Entomological survey in the historical focus of human African trypanosomiasis of Bendje (Gabon)]. / Enquête entomologique dans le foyer historique de trypanosomose humaine africaine de Bendjé (Gabon).

The situation of human African trypanosomiasis (sleeping sickness) is poorly known in Gabon. Most of the historical foci have not been investigated for more than 15 years. Few cases are passively recorded from the historical focus of Bendjé; they involved mainly fishermen but determining their contamination site is difficult because of their mobility due to their activity. The presence of these cases in that focus could favour its reactivation if the vector is still there. In order to assess a potential transmission risk in that area, an entomological survey has been carried out in it. Traps were set up during four days in different habitats used by humans during their daily activities. Three species of tsetse flies (Glossina palpalis palpalis, G. pallicera newsteadi and G. caliginea) were caught and two species of trypanosomes (Trypanosoma vivax and T. brucei s.l.) were identified by PCR. These results suggest the presence of an animal transmission cycle. Human-flies contact was confirmed in all type of habitats but no transmission was quantified in the mangrove.

Issues thérapeutiques des patients tuberculeux suivis dans les centres de dépistage et de traitement de la ville de Matadi, dans le contexte du VIH

Contexte. La tuberculose et l'infection a VIH/SIDA sont deux problemes majeurs de sante publique en Republique Democratique du Congo. Dans la lutte antituberculeuse; la co-infection VIH/TB pose un probleme en matiere de choix du regime therapeutique; du moment optimal du debut du traitement et pour l'issue du traitement antituberculeux. Cette etude vise a evaluer l'association entre le statut serologique VIH du patient; le traitement par anti-retroviraux (ARV); et l'issue therapeutique sous antituberculeux. Methodes. Une etude de cohorte retrospective portant sur 484 patients; avec tuberculose pulmonaire a frottis positif; depistes et suivis en 2008-2009; a ete realisee dans les 3 centres de sante de diagnostic et de traitement de la Zone de Sante de Matadi. Le test Khi-carre a permis de comparer l'association entre l'issue et la serologie VIH d'une part; et entre l'issue et le traitement antiretroviral pour les co-infectes d'autre part. Le risque relatif a permis de mesurer la force de ces associations. Resultats. L'etude a inclus 484 malades tuberculeux a frottis positif (261 hommes; 223femmes). Un malade tuberculeux sur dix etait VIH+ (10;5; IC95: 7;8- 13;2). Le taux de succes therapeutique parmi les tuberculeux VIH+ etait plus faible que celui des tuberculeux VIH- (72;6 vs 87;8; RR = 0;83[0;69 - 0;98]) et le taux d'issue defavorable parmi les tuberculeux VIH+ etait superieur a celui des tuberculeux VIH- (13;7 vs 6; RR = 2;29[1;04 - 4;99]). L'issue therapeutique des patients co-infectes n'est pas influencee par le traitement antiretroviral. Conclusion. Cette etude a montre que l'issue therapeutique de la tuberculose chez les sujets infectes par le VIH est moins favorable que celle des sujets seronegatifs. L'impact des ARV sur l'issue du traitement antituberculeux n'a pas ete clairement etabli

Prospects for the development of odour baits to control the tsetse flies Glossina tachinoides and G. palpalis s.l.

Field studies were done of the responses of Glossina palpalis palpalis in Côte d'Ivoire, and G. p. gambiensis and G. tachinoides in Burkina Faso, to odours from humans, cattle and pigs. Responses were measured either by baiting (1.) biconical traps or (2.) electrocuting black targets with natural host odours. The catch of G. tachinoides from traps was significantly enhanced ( approximately 5x) by odour from cattle but not humans. In contrast, catches from electric targets showed inconsistent results. For G. p. gambiensis both human and cattle odour increased (>2x) the trap catch significantly but not the catch from electric targets. For G. p. palpalis, odours from pigs and humans increased (approximately 5x) the numbers of tsetse attracted to the vicinity of the odour source but had little effect on landing or trap-entry. For G. tachinoides a blend of POCA (P = 3-n-propylphenol; O = 1-octen-3-ol; C = 4-methylphenol; A = acetone) alone or synthetic cattle odour (acetone, 1-octen-3-ol, 4-methylphenol and 3-n-propylphenol with carbon dioxide) consistently caught more tsetse than natural cattle odour. For G. p. gambiensis, POCA consistently increased catches from both traps and targets. For G. p. palpalis, doses of carbon dioxide similar to those produced by a host resulted in similar increases in attraction. Baiting traps with super-normal (approximately 500 mg/h) doses of acetone also consistently produced significant but slight (approximately 1.6x) increases in catches of male flies. The results suggest that odour-baited traps and insecticide-treated targets could assist the AU-Pan African Tsetse and Trypanosomiasis Eradication Campaign (PATTEC) in its current efforts to monitor and control Palpalis group tsetse in West Africa. For all three species, only approximately 50% of the flies attracted to the vicinity of the trap were actually caught by it, suggesting that better traps might be developed by an analysis of the visual responses and identification of any semiochemicals involved in short-range interaction.

Tsetse elimination: its interest and feasibility in the historical sleeping sickness focus of Loos islands, Guinea.

Guinea is the West African country which is currently the most prevalent for sleeping sickness. The littoral area is the region where most of the recent sleeping sickness cases have been described, especially the mangrove sleeping sickness foci of Dubreka and Boffa where Glossina palpalis gambiensis is the vector. Loos islands constitute a small archipelago 5 km apart from the capital, Conakry. Medical, animal, and entomological surveys were implemented in these islands in Oct-Nov 2006. No pathogenic trypanosomes were found in these surveys. The locally very high tsetse densities (up to more than 100 tsetse/trap/day) linked to pig rearing, constitute a high potential risk for humans (taking into account populations movements with neighboring active sleeping sickness foci of the Guinea littoral, and the history of sleeping sickness on these islands), and for the economically important pig rearing, as well as a danger for tourism. This situation, associated to the possibility of elimination of these tsetse populations due to low possibility of reinvasion, led the National Control Program to launch a tsetse elimination project following an "area wide" strategy for the first time in West Africa, which participates in the global objective of the PATTEC (Pan African Tsetse and Trypanosomosis Eradication Campaign).

[Eco-distribution and Trypanosoma infection of Glossina palpalis palpalis in the Banco forest of and its relics, Abidjan (Côte d'Ivoire)]. / Chorologie et infection par les trypanosomes de Glossina palpalis palpalis dans la forêt du Banco et ses reliques, Abidjan (Côte d'Ivoire).

In order to implement an anti-vector programme in the suburb of Abidjan (Côte d'Ivoire), investigations were conducted to assess the tsetse fly densities as well as infection with trypanosomes. Catches were carried out during the rainy season and dry season with Vavoua traps laid during four consecutive days in different sites (Banco forest, Abidjan zoological park, area of the University of Abobo-Adjamé). One species of tsetse fly (Glossina polpalis palpalis) and two species of trypanosomes (Trypanosoma congolense, T. vivax) have been revealed. The apparent density per trap per day (DAP) is very high in the zoological park, 54.8 tsetse fly/trap/day during the dry season and 28.1 during the rainy season. At the University of Abobo-Adjamé, the DAP is respectively 13.5 and 8.1 tsetse fly/trap/day during the rainy season, and in the dry season it is only 0.9 and 0.8 in the Banco Forest. The physiological age on all sites is as follows: 57.5 % of old parous, 39% of young parous and 3.6 % of nulliparous in the rainy season. These proportions vary to 51.9% of young porous, 47.1% of old parous and 1% of nulliparous in the dry season. The overall infection rate is estimated at 20.7% in the rainy season and 20% in the dry season. Statistical analysis have showed a significant difference in the distribution of infection rates.

Epidemiological study of canine trypanosomosis in an urban area of Ivory Coast.

Following confirmed cases of trypanosomosis in military working dogs, a cross-sectional study was undertaken to evaluate the source of infection and determine the prevalence of canine infection with Trypanosoma congolense in the urban focus of Abidjan, Ivory Coast. Blood from 123 dogs were collected and subjected to PCR using specific primers for Trypanosoma congolense "forest type". In addition, an entomological study was conducted in an urban area near the forest surronding the military camp. The observed prevalence was 30.1% and PCR positivity to Trypanosoma congolense was not significantly associated with sex or age of animals. This study demonstrates the high contamination rate of dogs in enzootic zones, the potential risk of introduction of the disease in free animal populations and the ability of Glossina palpalis to adapt to urban areas and to transmit trypanosomosis in such areas. The factors leading to a possible emergence of canine trypanosomiasis in enzootic zones need further investigations.

[One century of "sleeping sickness" in West Africa]. / Un siècle de "trypano" en Afrique de l'Ouest. Communication affichée lors des journées du centenaire de la SPE.

This paper summarizes the geography of sleeping sickness disease (or Human African Trypanosomiasis, HAT) over the last 100 years in West Africa, with the objective of identifying today's priority areas for the sleeping sickness surveillance. The history and geography of the disease are based on a bibliographic review of old reports and recent publications on recent results obtained from medical surveys conducted in West Africa up to 2007. This allowed us to situate the historical geography of HAT from the beginning of the 20th century to nowadays. For instance, active HAT foci seem to have moved from the North (savannah area) to the South (forest area) in the last century. Taking into account the limited nature of the information available, endemic HAT presently appears to be limited to areas where annual rainfall is higher than 1,200 mm, although the reasons for this remain unknown. During this period of time there has also been a shift towards the south of the isohyets and of the northern distribution limit of tsetse. Currently the most severely affected countries are Guinea and Ivory Coast, whereas the northern countries seem less affected, but many parts of West Africa still lack information on HAT and remain to be investigated. These observations, put back in the current context of demographic growth and climatic global change, responsible for landscape evolution, political instability and population movements, raise the question of HAT becoming.

[The impact of war on the evolution of sleeping sickness in west-central Côte d'Ivoire]. / L'impact de la guerre sur l'evolution de la THA dans le centre-ouest de la Côte d'Ivoire.

OBJECTIVE: To evaluate the situation of sleeping sickness in west-central Côte d'Ivoire from 2000 to 2003, in view of the war which broke out in September 2002. METHODS: Active surveys by medical teams and passive case detection. RESULTS: Between 2000 and 2003, 250 patients were diagnosed with sleeping sickness. At first it appeared that sleeping sickness prevalence had fallen since the beginning of political troubles. But this apparent drop was due to poor population coverage. Participation in medical surveys differed according to ethnic group, reflecting land use conflicts between ethnic communities. Such conflicts are common in this area, but have been exacerbated by the war. CONCLUSION: In war, assessing the importance of sleeping sickness by medical surveys only is very difficult. But detection of sleeping sickness cases by passive surveillance increased.

[Human African trypanosomiasis in the mangrove forest in Guinea: epidemiological and clinical features in two adjacent outbreak areas]. / La Trypanosomose Humaine Africaine en zone de mangrove en République de Guinée: caractéristiques épidémiologiques et cuniques de deux foyers voisins.

The purpose of this study carried out in two adjacent areas of the coastal mangrove forest of Guinea (Dubreka and Boffa) was to screen the population for disease, provide information on human African trypanosomiasis (HAT, a.k.a. sleeping sickness) and compare the epidemiologic and clinical features with those of outbreak areas in the Ivory Coast where more data is currently available. Cases of HAT were confirmed by parasitological testing after active medical work-up (91 of 9637 patients examined). Five cases were confirmed in patients in treatment centers. Of the first 57 cases admitted for treatment in the Dubreka and Boffa centers, 29 were responded to a clinical and epidemiological questionnaire and underwent thorough clinical examination. Disease stage was determined by cytochemical testing of cerebrospinal fluid. As in outbreak areas of the Ivory Coast, sleeping sickness in Dubreka and Boffa is a rural disease mainly affecting the working population. Most cases identified in Guinea involved men and women working in farming, fishing, or salt extraction. However unlike Ivory Coast outbreak areas where ethnic diversity related to share cropping is considered to play a major role in maintaining endemicity, almost all patients in our study (98%) were from the native Soussou population that is self employed and lives in villages with no immigrant population. While clinical symptoms observed in these patients were not different from those reported elsewhere, there was a high frequency of cervical adenopathy (93%). This finding could provide a useful diagnostic sign for screening populations living in these mangrove forest regions and as a source for parasitological diagnosis as shown by the fact that 88.5% of patients were screened on the basis of lymph node fluid specimens. Most patients including among those identified by active work-up (5%) were in the meningo-encephalitis phase of the disease (98%). The findings of this study underline the need not only to continue surveillance in these regions but also to extend surveillance throughout the country as a means of avoiding recrudescence and extension of the disease.

Mixed infections of trypanosomes in tsetse and pigs and their epidemiological significance in a sleeping sickness focus of Côte d'Ivoire.

In a sleeping sickness focus of Côte d'Ivoire, trypanosomes were characterized in humans, pigs and tsetse using various techniques. Out of 74 patients, all the 43 stocks isolated by KIVI (Kit for In Vitro Isolation) appeared to belong to only one zymodeme of Trypanosoma brucei gambiense group 1 (the major zymodeme Z3). The only stock isolated on rodents belonged to a different, new, zymodeme (Z50), of T. b. gambiense group 1. From 18 pigs sampled in the same locations as the patients, PCR showed a high proportion of mixed infections of T. brucei s. l. and T. congolense riverine-forest. Zymodemes of T. brucei s. l. from these pigs were different from those found in humans. From a total of 16 260 captured tsetse (Glossina palpalis palpalis), 1701 were dissected and 28% were found to be infected by trypanosomes. The most prevalent trypanosome was T. congolense riverine-forest type, followed by T. vivax, T. bruceis. l. and T. congolense savannah type, this latter being associated to the forest type of T. congolense in most cases. Mixed infections by 2 or 3 of these trypanosomes were also found. Use of a microsatellite marker allowed us to distinguish T. b. gambiense group 1 in some of the mature infections in tsetse. Differences in infection rates and in trypanosome genotypes according to the host might indicate that the pig may not be an active animal reservoir for humans in this focus.