Mapping of schistosome hybrids of the haematobium group in West and Central Africa.

Hybridization of parasitic species is an emerging health problem in the evolutionary profile of infectious disease, particularly within trematodes of the genus Schistosoma. Because the consequences of this hybridization are still relatively unknown, further studies are needed to clarify the epidemiology of the disease and the biology of hybrid schistosomes. In this article, we provide a detailed review of published results on schistosome hybrids of the haematobium group. Using a mapping approach, this review describes studies that have investigated hybridization in human (S. haematobium, S. guineensis, and S. intercalatum) and animal (S. bovis and S. curassoni) schistosome species in West Africa (Niger, Mali, Senegal, Côte d'Ivoire, Benin, Nigeria) and in Central Africa (Cameroon, Gabon, Democratic Republic of Congo), as well as their limitations linked to the underestimation of their distribution in Africa. This review provides information on studies that have highlighted hybrid species of the haematobium group and the regions where they have been found, notably in West and Central Africa.

[Epidemiological, clinical and evolutionary aspects of severe traumatic brain injury in the multipurpose intensive care unit of Gabriel Touré Teaching Hospital]. / Aspects epidemiologiques, cliniques et evolutifs des traumatises cranio-encephaliques graves au service de reanimation polyvalente du CHU Gabriel Toure.

Among traumas, cranial involvement occupies a special place due to their severity and the importance of the sequelae that they can cause. They are said to be serious when the Glasgow Scale (GCS) ≤ 8. The frequency of severe brain injury in the population in African studies ranges from 3.5 to 7. Mortality is, however, poorly known in developing countries, which led us to initiate this work, which aimed to study the epidemiological, clinical and evolutionary aspects of severe traumatic brain injury in the multipurpose intensive care unit of Gabriel Touré University Hospital. MATERIAL AND METHOD: 24-month retrospective study, descriptive and analytical, including all severe traumatic brain injury patients hospitalized in the resuscitation department of Gabriel Touré University Hospital during this study period. RESULTS: During the periodof 1165 patients admitted to the service, 72 were hospitalized for severe cranio-encephalic trauma for a prevalence of 6%. The age group of 21 - 40 years was the majority with (23) or 44.4% and the average age was 30.93 ± 18.8 years with extremes of 8 months and 79 years.The male sex was predominant with (65) or 90.3%, and a sex ratio of 9.28. During our study, (57) or 79.2% of serious traumatic brain injuries were due to road accidents with motorcycle-motorcycle collisions as a mechanism in (20) or 27.8%. Shopkeepers, and students were the most affected social strata with respectively (22) or 30.6% and (20) or 27.8%. Patient transport was provided by non-medical ambulances for (31) or 43.1% and admission time was between 30 minutes and 6 hours in (16) or 22.2% of cases. (62) or 86.1% had GCS between 6-8 and bilateral mydriasis was present in (10) or 13.9% of patients. (9)or 12.5% of patients had hypotension (systolic blood pressure<90 mm Hg) on admission and average blood pressure<90 mmHg was observed in (32) or 44.4% of patients. (23) or 31.9% had a SPO2 <90%. Cranio-encephalic scanning was performed in 62 or 86.1% and discovered as lesions (25) or 34.9% hemorrhagic contusions followed by extradural hematomas (13) or 18.1%. (63) or 87.5%, patients were intubated-ventilated-sedated in addition to resuscitation. (28) or 38.9% of patients had undergone a surgical intervention with (9) or 12.5% having osmotherapy.The evolution was marked by death of (48) or 66.7%. CONCLUSION: Severe cranio-encephalic trauma represents a major cause of morbidity and mortality. The establishment of pre-hospital medicine will allow better care and reduction of mortality by early and continuous management of ACSOS and respiratory and / or hemodynamic distress, which are very often associated with severe TCE.

Parmi les traumatismes, les atteintes crâniennes occupent une place particulière du fait de leur gravité et de l'importance des séquelles qu'elles peuvent entraîner. Ils sont dits graves quand le score de Glasgow (GCS) ≤ 8. La fréquence des traumatismes crânio-encéphaliques (TCE) graves au sein de la population dans les études africaines varie entre 3,5 et 7. La mortalité est cependant mal connue dans les pays en voie de développement ce qui nous a conduit à initier ce travail qui avait pour objetd'étudier les aspects épidémiologiques, cliniques et évolution des traumatisés crâniens graves au service de réanimation polyvalente du centre hospitalier universitaire Gabriel Touré. MATÉRIEL ET MÉTHODE: Etude, descriptive et analytique à collecte rétrospective s'étant déroulée sur 24 mois, incluant tous les patients traumatisés crânio-encéphaliques graves hospitalisés dans le service de réanimation du centre hospitalier universitaire Gabriel Touré durant cette période d'étude. RÉSULTATS: Durant la période sur 1165 patients admis dans le service.72 ont été hospitalisés pour traumatisme crânio-encéphalique grave soit une prévalence de 6%. La tranche d'âge de 21 - 40 ans était majoritaire avec(32) soit 44,4% et l'âge moyen était de 30,93 ±18,8 ans avec des extrêmes de 8 mois et 79 ans. Le sexe masculin était prédominant avec (65) soit 90,3%, et un sex-ratio de 9,28. Durant notre étude (57) soit 79,2% des TCE graves étaient dus aux accidents de la voie publique avec comme mécanisme les collisions moto-moto dans (20) soit27,8%. Les commerçants, et les élèves et étudiants étaient les couches sociales les plus touchées avec respectivement(22) soit 30,6% et (20) soit 27,8%. Le transport était assuré par des ambulances non médicalisées à(31) soit 43,1% et le délai d'admission était compris entre 30 minutes et 6 heures dans (16) soit 22,2% des cas.(62) soit 86,1% avaient GCS entre 6-8 et une mydriase bilatérale était présente chez (10) soit 13,9 % des patients. (9) soit 12,5% des patients avaient présenté une hypotension (pression artérielle systolique< 90 mm Hg) à l'admission et une pression artérielle systolique ≤ 90 mm Hg avait été observée chez (32) soit 44,4% des patients. Durant notre (23) soit 31,9% avaient une SPO2 < 90%. Le scanner cranio-encéphalique a été réalisé chez (62) soit 86,1% et retrouvait comme lésions, les contusions hémorragiques (25) soit 34,9% suivis des hématomes extraduraux (13) soit 18,1%.(63) soit 87,5% des patients ontété intubés -ventilés-sédatés en plus à des mesures de réanimation. (28) soit 38,9% des patients avaient subi une intervention chirurgicale associée chez (9) soit 12,5% à une osmothérapie. L'évolution a été marquée par une létalité de (48) soit 66,7%. CONCLUSION: Les traumatismes crânio-encéphaliques graves représentent une cause majeure de morbi-mortalité. La mise en place d'une médecine préhospitalière permettra une meilleure prise en charge et la réduction de lamortalité.Par une prise en charge précoce et continue des ACSOS et des détressés respiratoires et/ou hémodynamiques qui sont très souvent associées au TCE grave.

Status epilepticus in black African patients with hypertensive encephalopathy: a rare entity that must not be underrated.

The severity of a blood pressure spike is more closely associated with serious organ dysfunction, which can be life-threatening in the short term, than with the blood pressure level itself. A hypertensive emergency is defined as the presence of high blood pressure associated with acute organ dysfunction. The specific nature of high blood pressure in black patients may cause more frequent hypertensive emergencies. In this retrospective case study, we report our experience and highlight the specific prognosis for black African patients. We examined three patients, aged 27, 47, and 59 years, admitted to intensive care for a hypertensive emergency with neurological distress, and all in status epilepticus. Average blood pressure was 171 mm HG. Treatment included intubation, ventilation, and induction of a barbiturate coma, plus antihypertensive treatment. The outcome was favorable, with an average stay of 5 days. The frequency of hypertensive emergencies varies according to age, ethnic origin, and period studied. Black patients often suffer from more severe forms of high blood pressure, arising at an earlier age. Hypertensive encephalopathy can occur in patients with or without chronic hypertension. Without treatment, the encephalopathy induces a coma that can quickly become fatal. Its spontaneous course is catastrophic (10-20% survival at one year), but more favorable with adequate treatment (60-80% survival at five years).

Entomological and parasitological parameters of malaria transmission in Douguia, Chad.

Malaria remains a threat for many countries, especially in Chad where it is the leading cause of morbidity and mortality. Few reliable data exist, however, about the entomological and parasitological parameters of malaria transmission. The objective of this study was to investigate the entomological and parasitological parameters of malaria transmission in Douguia, a village located 75 km northeast of Ndjamena (Chad), as part of a training program for participants in Chad's malaria control program. Mosquitoes were collected after morning pyrethroid spraying, with a mouth aspirator. The parasitological data were collected by a rapid diagnosis test or microscopic examination. The study examined 350 subjects aged from 6 months to 80 years. The plasmodic index (PI) of Plasmodium falciparum was 25.4 % (n = 89) and the gametocygenic index (GI) 9.1 % (n = 32); they varied significantly from one age group to another (p = 10- 3). The PI in pregnant women attending antenatal clinics was 18.7 % (n = 12/64). Three Anopheles species were found: Anopheles gambiae s.l, An. arabiensis and An. pharoensis. An. coluzzii accounted for 94.9 % of the An. gambiae s.s. The antigen sporozoite index (SI) was 4.5 %. Our results confirm the endemicity of malaria in Chad (Douguia) and underline the major role of An. gambiae s.l. in its transmission. However, repeated studies using PCR for Plasmodium detection would help to improve our understanding of its epidemiology.

[Epidemiology of schistosomiasis in the periurban area of Sotuba, 10 years mass treatment began in Mali]. / Épidémiologie des schistosomoses dans le village périurbain de Sotuba, dix années après la mise à échelle du traitement de masse au Mali.

OBJECTIVE: The objective of this work was to describe the epidemiology of schistosomiasis 10 years after mass administration of praziquantel began in Sotuba, Mali. METHODOLOGY/RESULTS: This observational cross-sectional survey in Sotuba, a periurban village in the Bamako district, took place from July to September 2010 and collected stool and urine samples from residents at least one year old. Kato-Katz (for stool) and urine filtration techniques were used to detect Schistosoma mansoni and S. hæmatobium eggs, respectively. Overall, 335 urine samples and 300 stool samples were examined. The prevalence rate was 5.4% (18/335) for S. hæmatobium and 8.7% (26/300) for S. mansoni. Excretion of these eggs was most frequent in the 6-15 year-old group: 4.8% (16/335) for S. hæmatobium and 7.7% (23/300) for S. mansoni. Snails of the Biomphalaria pfeifferi and Bulinus truncatus species were the intermediate hosts, captured in the fields at water contact points. The principal clinical symptoms reported by participants were abdominal pain 27.2% (61/169) and headaches 23.2% (52/169). CONCLUSION: Despite the implementation of mass drug administration in Mali a decade ago, our results show that schistosomiasis transmission continues in Sotuba. Assessment of the risk factors for this persistent transmission is strongly needed.

Protein tyrosine phosphatase 1B negatively regulates S100A9-mediated lung damage during respiratory syncytial virus exacerbations.

Protein tyrosine phosphatase 1B (PTP1B) has anti-inflammatory potential but PTP1B responses are desensitized in the lung by prolonged cigarette smoke exposure. Here we investigate whether PTP1B expression affects lung disease severity during respiratory syncytial viral (RSV) exacerbations of chronic obstructive pulmonary disease (COPD). Ptp1b(-/-) mice infected with RSV exhibit exaggerated immune cell infiltration, damaged epithelial cell barriers, cytokine production, and increased apoptosis. Elevated expression of S100A9, a damage-associated molecular pattern molecule, was observed in the lungs of Ptp1b(-/-) mice during RSV infection. Utilizing a neutralizing anti-S100A9 IgG antibody, it was determined that extracellular S100A9 signaling significantly affects lung damage during RSV infection. Preexposure to cigarette smoke desensitized PTP1B activity that coincided with enhanced S100A9 secretion and inflammation in wild-type animals during RSV infection. S100A9 levels in human bronchoalveolar lavage fluid had an inverse relationship with lung function in healthy subjects, smokers, and COPD subjects. Fully differentiated human bronchial epithelial cells isolated from COPD donors cultured at the air liquid interface secreted more S100A9 than cells from healthy donors or smokers following RSV infection. Together, these findings show that reduced PTP1B responses contribute to disease symptoms in part by enhancing S100A9 expression during viral-associated COPD exacerbations.

[Lice in Mali: frequency of infestation, genotyping, infection rate and case management]. / Poux au Mali: fréquence de portage, génotypage, taux d'infection et prise en charge.

OBJECTIVES: Because lice-transmitted infections are a real public health problem, epidemiological studies in different ecoclimatic zones of Africa are useful. This article aims to describe the frequency of lice infestation, their genotypes, and their infection by pathogens in the regions of Koulikoro and Mopti. METHODOLOGY: A cross-sectional survey allowed us to collect lice from rural populations. Techniques of molecular biology (real-time PCR, standard PCR, and genotyping) were used for analysis of lice samples. RESULTS: Infestation rates were 57% (12/21) among subjects in Diankabou, in the Sahelian zone; 91% (39/43) in Doneguebougou, and 86% (59/69) in Zorocoro, in a savanna zone. The overall lice infestation rate in the samples in the three localities was 83% (110/133). Real-time PCR showed 3% (4/92) of Acinetobacter baumanii but no B. quintana in Diankabou. Phylogenetic analysis of the mitochondrial gene (Cytb) showed that head lice in Mali belong to genotype C. CONCLUSIONS: The high frequency of lice infestation in the study population indicates that it would be useful to conduct national epidemiological surveys to estimate the magnitude of this public health problem.

Type-I interferons induce lung protease responses following respiratory syncytial virus infection via RIG-I-like receptors.

The role of proteases in viral infection of the lung is poorly understood. Thus, we examined matrix metalloproteinases (MMPs) and cathepsin proteases in respiratory syncytial virus (RSV)-infected mouse lungs. RSV-induced gene expression for MMPs -2, -3, -7, -8, -9, -10, -12, -13, -14, -16, -17, -19, -20, -25, -27, and -28 and cathepsins B, C, E, G, H, K, L1, S, W, and Z in the airways of Friend leukemia virus B sensitive strain mice. Increased proteases were present in the bronchoalveolar lavage fluid (BALF) and lung tissue during infection. Mitochondrial antiviral-signaling protein (MAVS) and TIR-domain-containing adapter-inducing interferon-ß-deficient mice were exposed to RSV. Mavs-deficient mice had significantly lower expression of airway MMP-2, -3, -7, -8, -9, -10, -12, -13, and -28 and cathepsins C, G, K, S, W, and Z. In lung epithelial cells, retinoic acid-inducible gene-1 (RIG-I) was identified as the major RIG-I-like receptor required for RSV-induced protease expression via MAVS. Overexpression of RIG-I or treatment with interferon-ß in these cells induced MMP and cathepsin gene and protein expression. The significance of RIG-1 protease induction was demonstrated by the fact that inhibiting proteases with batimastat, E64 or ribavirin prevented airway hyperresponsiveness and enhanced viral clearance in RSV-infected mice.

[Epidemiological, clinical and therapeutics aspects of snakebites in the Gabriel-Touré and Kati national hospitals of Mali: a ten-year retrospective study]. / Aspects épidémiologiques, cliniques et thérapeutiques des morsures de serpent dans les hôpitaux nationaux Gabriel-Touré et de Kati du Mali: étude rétrospective sur dix ans.

A retrospective study has been performed on snakebites from January 1993 to December 2002 in the national hospitals Gabriel-Touré, in Bamako, and Kati. It aimed to establish a synthesis of epidemiological, clinical, and therapeutic aspects from snakebites. Eight hundred thirty-two snakebites were recorded during this period. Men were mostly represented: 72 versus 28% of women. The average age was 28 ± 18 years. Farmers were most affected (28%). Most bites occurred between 16 and 20 hours, during the fieldwork and pasture in 44% cases. Lower limbs (73.8%) were more involved than hands (25.8%). Although the type of snake has not been determined, the clinical picture was that of viper syndrome, the severity of which was assessed by the grade of bleeding, edema, renal involvement (15.8%), and neurological disorders (13.3%). Antivenom was administered to 40.6% of patients whose case fatality rate was 2.8%, whereas it was 8.1% in its absence. The case fatality rate associated with serum therapy varied according to the antivenin, 1.5% with the antivenoms manufactured in Europe and 4% with those manufactured in Asia. Five parturients had a favorable outcome with antivenom. The initial management was carried out by traditional healers in 49.7% of cases. The annual case fatality rate decreased gradually from 12% in 1995 to 3% in 2002. The incidence of snakebite is greatly underestimated in hospitals because of inadequate records.

[Seasonal variability of intestinal helminths and Schistosoma haematobium in a rural area of the Sahel in Mali]. / Variations saisonnières de l'infestation par les helminthes intestinaux et Schistosoma haematobium en zone rurale sahélienne au Mali

OBJECTIVE: The objective of this study was to determine the prevalence of intestinal helminths and Schistosoma haematobium before and after the rainy season in Pongonon, Mali. METHODS: Volunteers aged one year and above were included. The Kato-Katz method was used to detect eggs and cysts in stool samples, and Wattman filtration to detect S. haematobium eggs in urine samples. Two cross-sectional surveys were conducted in July and November 2007. RESULTS: In July (beginning of the rainy season), 304 volunteers were included; 278 were seen again in November (at the end of the rainy season). We found more intestinal helminths at the end of the rainy season (8.3%) compared to the beginning of the season (2.9%) (P = 0.01). There was no infection with S. haematobium in July but 7.6% in November (P < 0.001). The prevalence of intestinal helminths in children and adults was similar (P > 0.05), but the prevalence of infection with S. haematobium was higher in children aged 6 to 16 years (17/153) than in adults (2/74) (P = 0.02). CONCLUSION: Infections with helminth and S. Haematobium were both more prevalent at the end of the rainy season. Adults were infected as well as children and may constitute potential reservoirs of parasites. Effective control of these parasitic infections requires mass drug administration programs that take place during the seasons of high parasite egg excretion and that also include adult populations in some areas.

Dangerous scorpion fauna of Mali

Although the main Malian scorpion species of medical interest, Androctonus amoreuxi, is responsible for severe envenomings and perhaps some deaths, it has hitherto been considered not dangerous for humans. This population is located in the Saharian North-Eastern regions of Mali where it is accompanied by Leiurus quinquestriatus, a well known dangerous species of the Sahara. In the Gao district, divided by the Niger River, less desolate than the Tessalit and Kidal regions, one specimen of the dangerous species Androctonus australis was found. To summarize, Mali harbors at least three dangerous scorpion species: Leiurus quinquestriatus, Androctonus amoreuxi and A. australis, the latter recently having been identified in Mali for the first time. The absence of Androctonus aeneas is surprising in this context because it is found in neighboring countries (Algeria, Niger) and should be detected by new surveys. The possibility of preparing a single scorpion antivenom intended for Saharian and sub-Saharian populations is discussed.(AU)

Scorpion envenoming in the north of Mali (West Africa): epidemiological, clinical and therapeutic aspects.

Scorpion envenomation remains a poorly known problem in sub-Saharan Africa, particularly in Mali, where the incidence is high in Northern area of the country (Sahara desert). We conducted a prospective study in two district health centers, Kidal and Tessalit (North-east of Mali), to describe the epidemiological, clinical and therapeutic features of scorpion stings. This study consisted of an exhaustive follow-up from admission to discharge of all patients stung by scorpions. Of a total of 282 cases recorded during one year, 207 (73.4%) occurred in Kidal, and the remaining 75 (26.6%) took place in Tessalit. The annual incidence was significantly higher in Tessalit (437 cases/100,000 population/year) than in Kidal (243 cases/100,000 population/year) (p < 10⁻6). Two hundred two (71.6%) stings occurred inside human dwellings, 142 (50.4%) during sleeping/resting, especially in August. One hundred ninety-one (67.7%) were on the lower extremities. Nocturnal stings, 168 (59.6%), occurred more often than diurnal stings, 114 (40.4%). Most patients, 163 (57.8%), were admitted less than 1 h after being stung. Local pain at the sting site was the common primary complaint. However, moderate and severe clinical signs were significantly higher in children than in adults (p < 0.05). The death rate (3.9%) was higher in children (3.5%) than in adults (0.3%) (p = 8.10⁻6; RR = 0.90 [IC: 0.84-0.06]). Of the 22 scorpion species identified, 13 (59.1%) were Leiurus quinquestriiatus, 8 (36.4%) were Androctonus amoreuxi, and 1 (4.5%) specimen was Buthiscus bicalcaratus. From these species, L. quinquestriiatus and A. amoreuxi were responsible of stings. The medical treatment was only symptomatic, and one hundred twenty-eight (45.3%) patients received traditional remedies before seeking medical attention. Our findings suggest that scorpion stings are common in the north of Mali and are a significant threat to human health.

[Snakebites in the Sudanian and Sahelian zones of Mali: epidemiology, symptoms and treatment]. / Morsures de serpents en zone soudano-sahélienne du Mali epidémiologie, symptomatologie et traitement.

The purpose of this study was to document the epidemiology, symptoms and treatment of snake envenomation in Mali between 2005 and 2006. Data was collected using two methods, i.e., household surveys and retrospective surveys. Household surveys carried out in a village of 597 people showed that the annual average incidence was 164 snakebites per 100,000 inhabitants. Retrospective surveys were conducted in 35 healthcare facilities (5 regional hospitals and 30 district health centers) located in 5 parts of the country. Study periods ranged from 2 to 11 years depending on the location. The mean annual incidence of snakebite including dry-bites without envenomation was 27 per 100,000 inhabitants (range, 15-59). Hospital mortality was 4.7% (67/1433) (range, 2.2-6.7%). The population at risk consisted mainly of working men who accounted for 68.4% (980/1433). Patients between 15 and 30 years accounting for 41.2% (590/1433) of the sample were at highest risk for snakebite (chi2=9.96; p=6.10-3). The frequency of snakebite increased from 9.9% (142/1433) in Mopti in the North to 39.9% (572/1433) in Sikasso in the South (chi2=11.93; p=0,017). Snakebites most frequently occurred during the rainy season (56.6%) but only 0.68% of victims were referred to the health center. Hemorrhagic and inflammatory syndromes were the main complications of envenomation. Treatment was always symptomatic. Antivenom serum requirements ranged from 63 to 200 ampoules per year. Our results show that the frequency of snakebites remains grossly underestimated based on hospital data.

[Coverage rate and satisfaction of populations after mass treatment with praziquantel and albendazole in Mali]. / Taux de couverture et satisfaction des populations apres traitement de masse au praziquantel et a l'albendazole au Mali.

In Mali, schistosomiasis always remains a major public health problem. In 2005, mass treatment campaigns with praziquantel and albendazole have been organized in all endemic regions. The present study aimed to assess the impact of these mass treatment campaigns and the recipient's satisfaction in two endemic areas (Mopti and Ségou). It was a cross-sectional study with one passage from February to March 2006. The study carried out on political authorities (n=142), teachers and school administers (n=70), health workers (n=46), community distributors (n=33), community members (n=2170) and pupils (n=2480). We used Lot Quality Assurance Sample (LQAS) to determine treatment coverage and recipient's satisfaction. Two types of lots were considered, villages and schools. Questionnaires were used for investigation. In Ségou, the treatment rates varied from 100% at school level and in community in Bla district to 97.2% in the community of Ségou town. In Mopti, a treatment rate of 100% was observed in Bankass and Douentza both at school and in the community. The proportion of happiest individuals (to feel well) after the mass treatment campaign was 72.3% among pupils and 76.6% in the community. The results of this study suggest that the high treatment coverage rates observed during these campaigns should be sustained by a yearly chemotherapy strategy preceded by a community's health education programmes.

Prevalence and perception of schistosomiasis in irrigated rice field area in Mali.

Summary The aim of this work was to assess prevalence and clinic of schistosomiasis as well as the knowledge, attitude and practice (KAP) of populations living in the village of Molodo, a rice irrigated area of Mali. By cross sectional survey with a single passage, we enrolled 346 children aged of 7 to 14 years and 308 parents. The prevalence of Schistosoma haematobium and S. mansoni were respectively 72% and 68%. Micro-hematuria (Sy=86%; Sp=45%), urinary difficulty (Se=828% ; Sp=33%), high frequency of urine (Se=76% ; Sp=31%) and suspubians pain (Se=78% ; Sp=31%) associated with urinary schistosomiasis indicated that these symptoms could be relevant diagnosis signs. Similar observations could be considered as a good sign of diagnosis of intestinal schistosomiasis due to S. mansoni with abdominal pains (Se=75% ; Sp=36%), to have a fancy of stool (Se=75% ; Sp=32%), diarrhea (Se=71% ; Sp=32%), des conjunctival paleness (Se=85,% ; Sp=33%) et de spleen enlargement (Se=71% ; Sp=33%). The transmission patterns of schistosomiasis were not well known by populations, because only 15% of pupils and 38% of parents incriminated the canal and/or the 'fala" (the lake) as genitourinary bilharzias contamination source especially after bathing. The intestinal form was known by 11% of pupils and by 24% of parents. These results show that in spite of schistosomiasis endemic pattern, in this area, populations didn't know well this pathology.

Impact of mass chemotherapy with praziquantel on Schistosoma haematobium and Schistosoma mansoni infections in Office du Niger, Mali.

Aims This study was carried up to assess the impact of mass chemotherapy with praziquantel on the prevalence and intensity of Schistosoma haematobium and Schistosoma mansoni in Office du Niger. Materials and Methods It was a cross sectional study with two passages about which we compared a test group of 7 villages (n=2342) treated in 1989 to a control group of 7 villages (n=2263). Results One year after mass chemotherapy, baseline prevalence rates of Schistoosma haematobium, Schistoaoma mansoni and those of the double infection decreased by 50%, 54% and 62,9% respectively. The geometric mean egg counts of Schistosma haematobium (GMECSh) was reduced by 66.6% and that of Schistosoma mansoni (GMECSm) by 43.4%. However, in spite of mass treatment, the overall prevalence rates of Schistosoma haematobium and mansoni were always higher than 20% in young people aged of 6-19 years. Conclusion These data show that in irrigated area, efficacy of praziquantel is strongly affected by age. This persistance of infection in population raises up several questions according to host immunity, parasite biology and praziquantel efficacy.

Comparison of schistosome transmission in a single- and a double-cropped area in the rice irrigation scheme, 'Office du Niger', Mali.

Rice is becoming increasingly important as a staple food in West Africa and there is a need to increase production to meet the demand and one way to achieve this is to harvest two annual crops. It is possible that such intensified irrigation could affect transmission of schistosomes and this study attempts to compare schistosome transmission in single and double-cropped areas of an irrigation scheme, 'Office du Niger', in Mali. Double cropping has been practised for some years in the Niono area while in the Kolongotomo area still only a single crop is grown. Parasitological surveys conducted in 10 villages (5 from each of these 2 areas) showed that Schistosoma haematobium was less prevalent in the area with single cropping than in the area with double cropping. In order to compare transmission patterns between the two areas, all human-water contact sites around four villages (two from each area) were identified and included in transmission studies. From August 1996 to June 1997, eight surveys were conducted, at intervals of approximately 45 days, in each of these sites to record density of the intermediate hosts, density of infected snails, environmental factors (especially density of aquatic macrophytes), and frequency of human-water contacts. Although the data provide useful information on transmission patterns in Niono and Kolongotomo areas, they fail to demonstrate clear-cut differences in snail population dynamics and transmission patterns between the two areas. A key element in snail habitats in both areas is the abundance of aquatic macrophytes, especially the submerged species. Snail control using environmental modification should focus on controlling these plants in human-water contact sites.

[Transmission of schistosomiasis in an urban population and prevalence of intestinal helminthiasis in Bamako, Mali ]. / Transmission de la schistosomose urbaine et prévalence des helminthoses intestinales à Bamako, Mali.

Parasitological, malacological and anthropological studies were performed to assess the prevalence of Schistosoma haematobium and S. mansoni in schoolchildren living in the suburban area of Bamako. A total of 1017 schoolchildren aged 6-14 years were selected in two different areas between September 1997 and December 1999. In Djikoroni, the prevalence of S. haematobium and S. mansoni was 80.7% (339/420) and 22.8% (85/372) respectively. There was no significant difference of prevalence and intensity of infection with S. haematobium between schools, gender and age (p > 0.05), whereas, those of S. mansoni were higher in the vicinity of (+/- 100 m from) major sites where infected Biomphalaria pfeifferi were found (p < 0.001). In Niomirambougou, S. haematobium was prevalent in 46.7% (279/597) and S. mansoni in 28.2% (134/475). Boys and children aged 11-14 years were more infected (p < 0.001). Associated intestinal helminths (Hymenolepis nana, Necator americanus and Ascaris lumbricoides) were relatively scarce (prevalence < 1%). The prevalences of schistosome infected snails intermediate host were relatively high, 49.3% (100/203) in B. pfeifferi, 20.6% (88/138) in B. truncatus and 24.1% (7/29) in B. globosus. We recorded a total of 2514 water contacts about which 1130 in December and 1384 in January. Most of the children, 42.9% (1077/2511) were attracted to water bodies for bathing, swimming and playing, suggesting the lack of recreational facilities in these areas. Developing local control programmes in schools located in the vicinity of water bodies would contribute to break the parasite transmission cycle in Bamako.

[Evaluation and treatment of snake bites in Bancoumana village in Mali]. / Evaluation des morsures de serpent et de leur traitement dans le village de Bancoumana au Mali.

A retrospective study was conducted on the epidemiological patterns and treatment of snakebites in the village of Bancoumana, 60 km south-west from Bamako. We analysed a total of 17 cases (8 males and 9 females). The distribution of snakebite cases by gender and by age showed that among subjects aged 5 to 20 years, boys were more exposed than girls (6 vs. 2), whereas, in those of 21 years and above, females were more frequently bitten than males (7 vs. 2) (p = 0.04). The treatment was mainly based on the use of anti-inflammatories and antibiotics, and sometimes of saline, glucose or anti-tetanic serum. Vitamin K was used in 7 cases and no patient was treated specifically. The success of therapy mostly depended on the shortness of delay between the snakebite occurring and patient referral to the health centre, and the low rate of envenomation. All the patients referred the same day they were bitten were cured, whereas three persons referred to the health centre at D3, D7 and D43 after bite died. The surveillance parameters were oedema, bleeding and vomiting.

[Prevalence and perception of schistosomiasis in a periurban school of Bamako in Mali]. / Prévalence et perception de la schistosomose en milieu scolaire périurbain de Bamako au Mali.

The prevalence of urinary and intestinal schistosomiasis, the knowledge, attitude and practice (KAP) regarding the disease among both the children and their parents were investigated in Djikoroni para, a Suburban area of Bamako. The prevalence of Schistosoma haematobium and S. mansoni were respectively 69.8% and 8.7%. Compared with the girls, the boys were significantly more infected by S. haematobium (p = 5.10(-3)), but no difference between the sexes was observed for S. mansoni (p = 0.36). Interviews indicated that 88% of children and 91% of adults considered micro-haematuria as a pathology, but did not know anything about intestinal schistosomiasis. The low sensitivity of micro-haematuria (56.8%) and of the criterion "abdominal pains" (66.7%) indicated that they couldn't be relevant diagnosis signs. The symptoms and mode of transmission were generally well understood for S. haematobium but not for S. mansoni. The later parasite, its intermediate host and their interactions were unknown. The main man water contacts are bathing and playing in the Woyowayanko and in the Niger river. Inadequate perception of schistosomiasis contributes to maintain schistosomiasis at a high level of prevalence in Djikoroni.