Prevalence of hypertension and associated risk factors in Benin.

BACKGROUND: Hypertension is one of the main risk factors of cardiovascular diseases. There has been a lack of data on this risk factor in the general population in Benin. The aim of this study was to determine the prevalence of hypertension and identify the associated risk factors in Benin. METHODS: A cross-sectional study was conducted from July to August 2008 in Benin's 12 departments. The questionnaire and anthropometric measurements of the World Health Organization STEPWISE survey were used. The sample included 6853 subjects 25-64 years of age, randomly selected by five-stage random sampling. Blood pressure was measured using standard procedures. Data was processed and analyzed using EPI DATA and STATA 9.2 software. Prevalence levels were compared using Pearson's chi(2) and means with the Student t-test. Univariate and multivariate regression analysis, taking the sampling method into account, was used to identify risk factors. RESULTS: The sample comprised 49.5% females, the 25- to 34-year-old age group was the largest, and the mean age was 42.7±12.4 years. The prevalence of hypertension was 27.9% [95% CI: 26.3-29.5%], 77.5% of the subjects were unaware of their high blood pressure, and 81.6% had not taken their drugs two weeks before the survey. Prevalence of known hypertension was 6.9%, prevalence of treated hypertension 4.8%, and prevalence of controlled hypertension 1.9%. Age and obesity were significantly associated with hypertension. Department and profession were not associated with hypertension. CONCLUSION: This study showed a high prevalence of hypertension in the general population in Benin. Better management of this risk factor will contribute to reducing morbidity and mortality due to cardiovascular diseases.

[Epidemiologic and medico-clinical aspects of the cholera outbreak in the Littoral department of Benin in 2008]. / Aspects épidémiologiques et médico-cliniques de l'épidémie de choléra dans le département du Littoral au Bénin en 2008.

OBJECTIVE: The purpose of this study was to determine epidemiological and medico-clinical features of the cholera outbreak that occurred in the Littoral department of Benin in 2008. METHODS: This cross-sectional descriptive analytic study was based on review of a total of 404 patient files. Study data included patient identity, clinical and therapeutic features and treatment outcome. Ten randomly selected patients participated in a focus group discussion. Decision-makers in charge of managing the outbreak and medical personnel that provided care were thoroughly debriefed and 10 affected areas were visited. Data were analyzed using EPI INFO 3.3.2 and EXCEL 2007. RESULTS: The outbreak started in Cotonou on 26 July 2008 and lasted for 21 weeks. Mean patient age was 23.72 +/- 14.80 years. Attack rates per district ranged from 15.86 to 172.98 per 100.000. Attack rates in Agbodjèdo, Hlacomey and Enagnon districts were significantly higher (p<10(-4)) than in other districts. The case fatality rate was 0.24 per 100. Crowded living conditions along the banks of the Cotonou lagoon along with poor sanitation and inadequate drinking water supply explain the endemicity of cholera in Cotonou. Vibrio cholerae O:1 was detected in 19 out of 36 stool samples. All strains were sensitive to ciprofloxacine but resistant to cotrimoxazole. Diarrhea was a consistent feature in all patients, along with vomiting in 88.11% and severe dehydration in 39.35%. Treatment involved oral rehydration, parenteral rehydration and antibiotherapy in 99.50%, 85% and 97.77% patients respectively. Antibiotherapy consisted of doxycycline for adult cases and amoxicilline for pregnant women and children. The duration of stay at the treatment center was significantly longer for patients with severe dehydration (p<10(-4)). CONCLUSION: Enhancing basic sanitation and access to drinking water and intensifying information campaigns on the need for healthy living behavior especially in districts located near the banks of Cotonou lagoon are needed to improve cholera prevention in the Littoral department in Benin.

[An outline of a method for estimating the calculated economic cost of malaria cases: its application to a rural area in Burkina Faso (Western Africa)]. / Esquisse d'une méthode d'estimation du coût économique chiffré des accès palustres: application à une zone rurale au Burkina Faso (Afrique de l'Ouest).

A precise method to estimate the cost of malaria in a rural area was developed and applied in 3 villages in Burkina Faso. The estimate takes into account direct costs such as consultation fees, microscopic examinations, medication and transport as well as indirect costs caused by lost work-days. The formula uses 6 variables: age of subject, degree of invalidity, duration of illness, profession, income and percentage of income lost. In the region of Bobo-Dioulasso, 3065 health centre clients were registered in the course of the study: 17% had been clinically diagnosed as having malaria but this was confirmed microscopically in only 11.6% of cases; 73.1% were children aged < 5 years, 13.9% children aged 6-15 years, 12.2% adults aged 16-50 years and 0.8% adults aged > 50 years. Most patients worked in agriculture and trade. The average duration of illness was 4 days, with each case incurring a cost of $11.7 comprised of $8 direct costs and $3.7 indirect costs.

[Malaria morbidity in adults living in urban Burkina Faso]. / Morbidité palustre, notamment chez l'adulte, en milieu urbain au Burkina Faso.

Urbanization in countries located in areas of endemic malaria can decrease the level of immunization and make malaria a more serious public health problem in adults. The purpose of this prospective study was to describe the clinical and parasitological features of malaria in adults in the city of Bobo Dioulasso in Burkina Faso. Study was carried out between July and November 1992 at the medical testing laboratory of the Muraz Center in 494 patients including 378 adults and 116 children under the age of 15 years. The parasitic index was 23% in adults as compared to 62% in children. There was not a significant difference in the parasitic index according to whether the place of residence was located in the city center or outlying suburbs. Parasite density ranged from 6 to 145,000 parasites per mm3 in adults as compared to 6 to 426,000 parasites per mm3 in children. Median parasitemia was 696 parasites per mm3 in adults as compared to 8800 per mm3 in children. The threshold of parasitemia for appearance of clinical symptoms was thus lower in adults than in children. Because of the poor positive predictive value of the main clinical features and the high incidence of self-treatment, microscopic examination is indispensable to confirm diagnosis of malaria. The results of this study indicate that urbanization in the city of Bobo Dioulasso has not significantly changed the level of immunization to malaria in adults.

[Spatial distribution of cancer incidence by anatomic site in Quebec]. / Distribution spatiale de sieges anatomiques choisis de cancer au Quebec.

Knowledge of the spatial distribution of diseases provides useful information in etiologic research and in implementation of preventive activities in community health. Spatial autocorrelation analysis is one of the various methods that enables to determine spatial clustering of diseases. This method has not been applied to lung, stomach and colon cancer in Québec. These cancers are frequent and are associated with environmental factors. The objectives of the study are to determine spatial distribution of incidence rates of these cancer sites by sex and to help generate etiologic hypotheses. Community health departments (CHDs) of residence are considered as risk markers since their population and environment may be related to the selected cancer sites. Data were obtained from Québec Cancer Registry. Rates were standardized by the direct method. Autocorrelation analysis was done through BW coefficient and Moran's coefficient I for correlograms. Results of standardized rates were compared to those of non standardized rates. Rates yielded the same results for the BW coefficient. Conversely, results were quite different for the correlograms. This implies that results from standardized rates should be kept since the age structure of CHD populations are different. Important variation in the level of spatial autocorrelation was found among the six sex-specific cancer sites. For male lung cancer and male stomach cancer first-order neighbouring CHDs showed similar incidence rates according to a geographic gradient. Female lung cancer exhibited spatial autocorrelation. Absence of spatial autocorrelation for colon cancer suggests that CHD is not the appropriate scale for study of this cancer and allows use of conventional epidemiologic methods. These results are discussed in relation to current etiologic hypotheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Situation de la chimioresistance du paludisme dans les Etats membres de l'OCCGE de 1991 a 1994

La chimioresistance du paludisme depuis son apparition dans les pays de l'OCCGE vers la fin des annees 1980 fait l'objet d'une surveillance organisee en reseau sous la coordination du CRCP (Centre de Reference de la Chimioresistance du Paludisme). La situation de la chimioresistance du paludisme dans ces pays de 1991 a 1994 a ete dressee a la suite des ateliers de 1993 et 1995

[Variation of the parasite density of Plasmodium falciparum in asymptomatic carriers: consequences for malaria chemoresistance studies]. / Variation de la densité parasitaire de Plasmodium falciparum chez des porteurs asymptomatiques: conséquences dans les études de chimiorésistance du paludisme.

During the studies on malaria chemoresistance, we noted great variations in parasite density of Plasmodium falciparum between screening in the morning and final selection in the afternoon, in asymptomatic people. To better understand this phenomenon, we conducted a study in october 1987 on primary school children in a village near the city of Bobo-Dioulasso, at the peak malaria prevalence. We performed 3 blood-smears at 8 a.m., 2 p.m. and 8 p.m., on Day 0 and Day 4, to an initial number of 86 children, aged from 6 to 9 years. By the end of the study 44 children remained who fulfilled the inclusion criteria Among them 35 showed a parasitaemia on Day 0 and 9 remained negative. On Day 4, 28 were positive and 16 remained negative. Of the 35 children positive at entry to the study 16 remained continuously positive, the others were negative on at least one occasion. Of the 28 children positive on Day 4, 14 remained continuously positive. For the 16 people with a parasitaemia continuously positive on Day 0.7 (43.7 p. cent) became spontaneously negative on Day 4. But considering the small size of our sample, the analysis of the nycthemeral variation and of the variation between the two days did not show a significant difference. Further studies involving a greater number of blood-smears during a longer period and concerning more people, should be conducted. The possibility of spontaneous negativation of the parasitaemia without drug absorption shows that there are some cases of false malaria chemosensitivity that are declared when the in vivo tests are not coupled with in vitro tests.

La chimioresistance du paludisme en Afrique de l'Ouest : situation actuelle dans les Etats de l'OCCGE

Dans le cadre du reseau de surveillance de la chimioresistance du paludisme dans les Etats de l'OCCGE; des enquetes de chimioresistance ont ete menees par les equipes nationales. les tests d'etude in vivo ont principalement ete utilises en enquete de surveillance passive. Les sujets autochtones; generalement les enfants d'age scolaire; ont ete etudies. La chloroquinoresistance decelee chez ces sujets en 1987 au Benin a ete observee la meme annee au Togo et en Cote d'Ivoire. Durant l'annee 1988 elle est apparue au Senegal et au Burkina Faso. Elle a ete notee en 1989 au Niger et en 1990 au Mali. Seule la Mauritanie est encore epargnee. Les caracteristiques de cette resistance chez les sujets autochtones sont decrites. La resistance est surtout parasitologique et en moyenne; son taux se situe au dessous de 50 pour cent

[Dracunculosis control by three techniques in the south-west of Burkina Faso. Compared efficacy of the techniques]. / Contrôle de la dracunculose par trois techniques au Sud-Ouest du Burkina Faso. Efficacité comparée des techniques.

A study on the effectiveness of health education, chemical treatment of water sources and the two combined measures was carried out in ten dracunculiasis endemic villages in South-Western Burkina Faso from 1985 to 1989. Data on cases were collected by active case-finding. Dracunculiasis was eliminated from four villages through health education and from four other through combined measures after four years. Endemy was reduced by 67 p. 100 in two villages through chemical treatment. Difficulties encountered in the setting up of the measures and place of each of them in control programs are discussed.

[Current aspects of malarial chemoresistance of subjects autochthonous in the OCCGE countries (West Africa)]. / Point actuel sur la chimiorésistance du paludisme des sujets autochtones dans les états de l'OCCGE (Afrique de l'Ouest).

Within the context of the monitoring of malaria drug resistance in the countries of the OCCGE, a workshop has been organized in order to sum up the surveys carried out by the national teams. For active or passive monitoring mainly the in vivo tests have been used. The native population, mainly school children, was studied. Chloroquine resistance was detected in 1987 in Benin, and in the same year in Togo and Côte d'Ivoire. During 1988 it appeared in Senegal and Burkina Faso, in 1989 in Niger and in 1990 in Mali. Only Mauritania is as yet free of resistance. The main features of this resistance are described. It is above all parasitological and on average its rate is less than 30%.

[Preliminary epidemiological study of dracunculosis in the southwest of Burkina Faso]. / Etude épidémiologique préliminaire de la dracunculose au sud-ouest du Burkina Faso.

An epidemiologic survey was carried out before the setting up of an applied research project on dracunculiasis control through three strategies. The data were collected by house-to-house visits and from family cards. The overall incidence rate was 10.3 per cent + 0.9 with variations from 1.7 to 35 per cent according to the villages. The incidence rates were significantly higher in the 5-14 and 15-59 years age groups. On the opposite, there was no significant difference between the rates according to sex. The disease presented a family feature and cases were concentrated in 35 per cent of families. The proportion of polyparasitism was important more than half of patients had two or more worms. The measurement of the same indicators at the end of project will allow the assessment of the project results.

[Vaccination against malaria: initial trial with an ant-sporozoite vaccine, (NANP)3-TT (RO 40-2361) in Africa (Bobo-Dioulasso, Burkina Faso)]. / Vaccination contre le paludisme: premier essai avec un vaccin antisporozoïte, le (NANP)3-TT (RO 40-2361) en Afrique (Bobo-Dioulasso, Burkina Faso).

The vaccine (NANP)3-TT is a synthetic peptide of the circumsporozoite protein (CS) of Plasmodium falciparum coupled to tetanus toxoid (TT) as protein carrier and adsorbed to aluminium hydroxide as adjuvant. The objectives of the study were to assess the immunogenicity and the protective efficacy of the vaccine in an area where malaria is endemic. The study was conducted in a zone of irrigated rice cultivation known as the Vallée du Kou to the North of Bobo-Dioulasso. Malaria transmission is permanent in the Vallée with maxima in July and November. The study was conducted from June to December 1988. It was a controlled randomised, double blind, prospective vaccine trial. A total of 123 infants from 3 to 5 months of age were randomly assigned to three groups. Group I (controls) received three doses of TT alone, group II received two doses of TT and one of (NANP)3-TT and group III received three doses of (NANP)3-TT. These vaccines were administered simultaneously with the Enlarged Program of Immunisation (EPI) vaccines. The clinical parasitological and immunological status of the children was then monitored over a period of five months. No systemic reactions to the vaccine were observed in the infants either immediately after administration or during the follow-up. Minor local tumefactions were observed in only 3% of the children. The vaccine was found to be immunogenic with a peak IgG response at day 75, when 56% (group II) and 60% (group III) showed antibody titres of at least four times that seen at day 0. The response, however, was a short duration; by day 150 the average antibody titres were not significantly different between the three groups. The incidence and the level of parasiaemia and the incidence of clinical malaria were also not significantly different for each of the three groups during the period of the study. The association of (NANP)3 with tetanus toxoid was not shown to be immunologically inhibitive. The results, despite not showing a protective effect for the vaccine (NANP)3-TT, have shown its immunogenicity and therefore suggest that further development of this vaccine may be worthwhile.

[Emergence of chloroquine-resistant malaria in West Africa: the case of Sokode (Togo)]. / Emergence du paludisme chloroquinoresistant en Afrique de l'Ouest: cas de Sokodé (Togo).

Within the framework of its surveillance of Plasmodium falciparum chloroquine sensitivity in eight West African countries (Benin, Burkina Faso, Côte d'lvoire, Mali, Mauritany, Niger, Senegal, and Togo) the Reference Centre for Chemoresistant Malaria (CRCP) at the Organization for Coordination and Cooperation to Control Major Endemic Diseases (O.C.C.G.E.) conducted an in vivo survey in February, 1987, in Sokodé (Togo). Two groups of 67 children, aged 2 to 9, received, for the first group a single 10 mg/kg dose of chloroquine; for the second group a 3-day 25 mg/kg dose, according to the WHO methodology. Thick and thin blood smears were examined on D0, D2, D3 when necessary, D4 and D7. Within the 23 children who received the 10 mg/kg dose, seven (30.4%) presented a "resistance", of which six were early RI type and 1 was RII type. Out of 44 children who received the standard dose of 25 mg/kg, two (4.6%) were resistant (early RI type resistance). These data show for the first time the appearance of in vivo chloroquine resistance in this country, and call for a withdrawal of the 10 mg/kg dose of chloroquine in the treatment of fever attacks to the benefit of a 25 mg/kg dose. Thorough studies, using in vivo and in vitro techniques, should be undertaken as soon as possible, not only in Togo but in other West African countries too, to take the exact measure of the issue.

[Filarial multiparasitism in the savannah zone in Burkina Faso]. / Etude du polyparasitisme filarien en zone de savane au Burkina Faso.

From june 1985 to may 1986, 1.209 consulting patients were examined for filariae in skin and blood. Among patients with microfilariae 17% had associations of filarial infections. The multiple infections rate seemed more important in man than woman and increased with age. The results showed that associations were not due to chance only. The frequencies of associations between Dipetalonema perstans and Onchocerca volvulus at one hand, Dipetalonema perstans and Wuchereria bancrofti on the other hand were highly significant. Symptoms of filarial associations were studied and subsequent therapeutic attitude discussed.

[Dracunculosis: beliefs and attitudes of populations in the endemic zone of the savannah (Burkina-Faso)]. / Dracunculose: étude des croyances et attitudes des populations en zone endémique de savane (Burkina-Faso).

For years, most of the authors propose the sinking of wells as the only method of dracunculiasis control. However, this measure did not lead to the eradication of this very vulnerable endemic scourge in West Africa. Our research has concerned the collection of epidemiologic and socio-medical data close to the housewives. The research has been carried out into six endemic villages in Burkina-Faso, North-Western savannah before the setting up of a control project through health education and chemical water supply points treatment. The global dracunculiasis incidence rate is about 20.3%, setting the six villages in hyperendemic zone. The family incidence rates are from 5.3% to 100% with an attack of 72% of families. The majority of patients are taken into account in case of disability by the village community. Causes of the illness are unknown for 68% of persons, but 30% of people associate it to the water. Ignorance and lack of treatment concern 63.5% of answers. Traditional treatment (32.8% of answers) is very diversified and based on plant extracts. As for the prevention of disease, there is no solution in 83% of cases. A part from the 35% of answers concerning modern well water, the other proposed methods are ineffective. Ponds are finally the mainly water supply source during the raining seasons in spite of the presence of modern wells. The reasons of that situation are mainly the taste of ponds water and the remoteness of wells. The understanding of those beliefs and attitudes lead to thing of several complementary strategies as sinking of modern wells and health education for dracunculiasis control.

[The OCCGE (Organisation de Coordination et de Coopération pour la Lutte contre les Grandes Endémies) and the surveillance of the drug sensitivity of Plasmodium falciparum to antimalarials]. / L'O.C.C.G.E. et la surveillance de la chimiosensibilité de Plasmodium falciparum aux antipaludéens.

Spreading of chemoresistance from East Africa to Central Africa is a very worrying problem for Western Africa. In fact, chemotherapy of febrile attacks is at present admitted as malaria control strategy in the framework of Primary Health Care. This new strategy is based on the fact that commonly used antimalarial drugs as chloroquine are surely efficacious. Thus, the surveillance of chemosensitivity of Plasmodium falciparum local strains becomes a priority. From studies carried out in Burkina Faso during many years, Centre Muraz of O.C.C.G.E. has organized a surveillance system with several levels: a Reference Center, a National Center for each country and sentinel centers located in the different epidemiological features of the countries. This surveillance concerning many states can allow to detect more quickly some possible problems in relation with chemoresistance and to take measures to limit its impact.

[Longitudinal study of Cyclopidae, intermediary hosts of the Guinea worm in the Sudano-Sahelian area (Burkina Faso)]. / Etude longitudinale des Cyclopidés, hôtes intermédiaires du ver de Guinée en zone soudano-sahélienne (Burkina Faso).

During 18 months covering two annual rainy seasons, 338 monthly water samples were taken in 29 ponds of two dracunculosis endemic villages of south-western Burkina Faso. The dynamics of ponds inhabited by Cyclopidae has been surveyed as far as their densities and their species are concerned. We identified a total number of 17 species from 6 genera of which the decreasing order in frequency is: Thermocyclops, Mesocyclops, Metacyclops, Cryptocyclops, Microcyclops and Allocyclops. The dominant species are: Thermocyclops crassus consimilis, Metacyclops margaretae, Thermocyclops oblongatus and Thermocyclops neglectus decipiens. The crowds of these major species during the period of dracunculosis high transmission in the surveyed area (June to July), suggest, in the absence of a search for Dracunculus medinensis larvae, that, they should play the principal part as vector of the parasite in this area.

[Dracunculosis, a scourge eradicated from 3 villages of Burkina Faso through health education]. / La dracunculose, un fléau éradiqueé dans trois villages du Burkina Faso par l'éducation sanitaire.

We carried out a dracunculiasis control study through health education in three southwestern hyperendemic villages of Burkina Faso. The villages were organized in the framework of Primary Health Care. Two years after the beginning of health education the sickness was eradicated. Feasibility, low cost and acceptability by populations of health education make it a main part of any dracunculiasis control strategy.

Atelier sur la chimioresistance du paludisme dans les etats de l'OCCGE : rapport final

Le Paludisme est une des endemies majeures pour laquelle le Centre Muraz de l'OCCGE consacre depuis sa creation en 1939 d'enormes efforts de recherche et de lutte. S'il est vrai que les cas de resistance clinique restent encore rares; leur accroissement rapide ne saurait tarder avec une expectative passive; et une anarchie des attitudes therapeutiques favorisee par l'introduction injustifiee des nouveaux antipaludiques. Le present document est le rapport final des travaux du 1er atelier regroupant des stagiaires formes par le Centre Muraz de l'OCCGE et qui s'est tenu les 4 et 5 mars 1991 a Bobo-Dioulasso. L'interet et l'utilite du Centre de Reference de la Chimioresistance du Paludisme (CRCP) du Centre Muraz ont ete vivement exprimes par tous les participants. En le dotant de moyens lui permettant d'assurer une coordination plus dynamique; une telle structure sera un catalyseur indispensable au developpement de la lutte antipaludique en general et a celle de la surveillance de la chimioresistance en particulier. Il a ete instamment recommande a l'OMS-AFRO d'en faire un centre collaborateur