[Prevalence of dental caries among 12-year old schoolchildren in the Dakar region]. / Prévalence de la carie dentaire chez les élèves de 12 ans de la région de Dakar.

Oral diseases are considered as major public health problem. Dental caries restricts the school activities and are the dominant cause of dental morbidity. The aims of this survey were to determine prevalence of dental caries among pupils of Dakar and to study their food habits and oral hygiene. A descriptive transversal study was conducted from February 15th to May 07th, 2011 with respect of WHO directives (protocol of 1997) readjusted to Senegalese context. Our results showed a prevalence of 41.8%; a mean DMF index of 0.644; a proportion of teeth decayed of 65%, 32.2% for missing teeth and 2.7% of filled teeth. The multivariate logistic regression analysis showed that snacking, consumption of sweetened drinks far from meals and brushing teeth before the meals were significantly linked to the presence of dental caries. These results showed that the state of oral health and the prevention level of dental caries among these children were not so good. A new orientation of oral health policy based on messages regarding the main etiologic factors is imperative.

[Prevalence of dental caries: national pilot study comparing the severity of decay (CAO) vs ICDAS index in Senegal]. / Prévalence de la carie dentaire: étude pilote nationale comparant l'indice de sévérité de la carie (CAO) vs ICDAS au Sénégal.

UNLABELLED: This pilot study has for main objective to measure the applicability and the utility of ICDAS index in a context of prevention in developing countries. Dental caries prevalence was evaluated among schoolchildren using DMF (WHO basic method) vs. ICDAS index in Senegal. MATERIALS AND METHOD: A representative stratified random cluster sample of 677 primary and college schoolchildren aged 12 and 15 years was examined for caries prevalence. The clinical examination was conducted in two steps for each. The investigator proceeded at first to the inventory of the number of teeth decayed (D), missing (M) or filled (F) according to the WHO basic method. Then, after cleaning and drying all teeth, a two-digit ICDAS code was used to record data at each dental surface. RESULTS: Caries prevalence (96%) was higher than expected in Senegal. ICDAS index provides 43% moreover information than DMF. The need for prevention (ICDAS1: 66%/72% and ICDAS2: 54%/58%) and intercept (ICDAS3: 40%/42% and ICDAS4: 31%/33%) are higher than the need of curative treatment (ICDAS5: 18%/23% and ICDAS6: 27%/33%) respectively among primary and college schoolchildren. CONCLUSION: Preventive programs are urgently needed in Senegal. It's necessary to lead epidemiological studies in other African countries for determining caries prevalence using the ICDAS criteria to harmonize oral health regional planning.

[Relationships between masticatory performance and nutritional state in complete denture wearers]. / Relations entre Performance Masticatrice et Etat Nutritionnel chez des Sujets Porteurs de Prothèses Complètes.

UNLABELLED: For many authors masticatory dysfunctions are related to reduction in dietary intake with malnutrition as a possible consequence. The aim of the present study was to further investigate the relationships between masticatory performance and nutritional state in complete denture wearers. METHOD: Masticatory performance was assessed using a granulometric method in 74 subjects divided into 2 subgroups according to their dental status (normal dentition and complete dental wearers). Nutritional status of study subjects was analyzed with Mini Nutritional Assessment (MNA). RESULTS: There were a significant association between wearing denture and Nutritional Status as assessed by MNA. Using this scale, a risk of malnutrition was found in 80% of subjects wearing complete denture and in 26% in the normal dentition sub group (p < 0.0001). There were also a positive and significant correlation between, the particle size distribution and masticated test food and nutritional status. CONCLUSION: Complete denture wearers are at greater risk of malnutrition than did subjects with normal dentition.

[Study of mastication in denture wearers among various ages]. / Etude des parametres physiologiques de la mastication chez des sujets ages porteurs de protheses adjointes completes.

INTRODUCTION: Recent studies have shown that it was possible for subjects with masticatory deficiency chewing achieve a satisfactory level of fragmentation of food by acting on some physiological parameters as the number of cycles and the time devoted to a sequence of mastication. METHOD: The objective of this work is to study the effects of the wearing of complete prostheses, of ageing on the physiological parameters from the chewing on a population of 110 subjects. RESULTS: The results show an important effect of the dental status. Indeed denture weaers need twice more cycles than controls of the same age to make a ham portion ready to be swallowed. Significant an age effect with regard to the number of cycles was also noted. The rheology of food affects the number of cycles which increases with the hardness of food.

[Study of the characteristics of the food bolus in elderly subjects with complete dentures]. / Etude des caractristiques du bol alimentaire chez des sujets agés porteurs de prothèses complètes.

Many studies have shown that wearing of complete dentures impairs masticatory function. The aim of this study was to investigate the influence of complete denture wearing and ageing on masticatory performance. Masticatory performance was assessed by a granulometric method on 110 subjects divided into 3 groups according to dental state and age. The results show edentulous subjects have a masticatory performance worse than their congeneric of the same age. Indeed, the median of the distribution of the size of the particles is more important at the carriers of prostheses than at the toothed old subjects (P < 0.0001). On the other hand the extent of the distribution does not vary significantly between these 2 groups of subjects. The parameters of the masticatory performance do not vary in a statistically significant way between the old subjects and the young controls. There is thus no significant effect of the age on the parameters of the performance masticatory.

Multicenter study of street foods in 13 towns on four continents by the food and environmental hygiene study group of the international network of pasteur and associated institutes.

An international multicenter study of ready-to-eat foods, sandwiches, and ice creams or sorbets sold in the streets and their vendors was carried out to assess the microbiological quality of these foods and to identify characteristics of the vendors possibly associated with pathogens. Thirteen towns in Africa, America, Asia, and Oceania were involved in the study. A single protocol was used in all 13 centers: representative sampling was by random selection of vendors and a sample of foods bought from each of these vendors at a time and date selected at random. Microbiological analyses were carried out using standardized Association Française de Normalisation methods, and the use of a standardized questionnaire to collect data concerning the characteristics of the vendors. Fifteen surveys were carried out, with 3,003 food samples from 1,268 vendors. The proportion of unsatisfactory food samples was between 12.7 and 82.9% for ice creams and sorbets and between 11.3 and 92% for sandwiches. For ice creams and sorbets, the sale of a large number of units (>80 per day) increased the risk of unsatisfactory food by a factor of 2.8 (95% confidence interval [CI]: 1.5 to 5.1), lack of training in food hygiene by 6.6 (95% CI: 1.1 to 50). and by a factor of 2.8 (95% CI: 1.4 to 5.4) for mobile vendors. These risk factors were not identified for sandwiches, this difference may be due to the presence of a cooking step in their preparation. These results show that the poor microbiological quality of these street foods constitutes a potential hazard to public health, that the extent of this hazard varies between the cities studied, and that vendors' health education in food safety is a crucial factor in the prevention of foodborne infections.

Parameters underlying successful protection with live attenuated mutants in experimental shigellosis.

Because the use of live attenuated mutants of Shigella spp. represents a promising approach to protection against bacillary dysentery (M. E. Etherridge, A. T. M. Shamsul Hoque, and D. A. Sack, Lab. Anim. Sci. 46:61-66, 1996), it becomes essential to rationalize this approach in animal models in order to optimize attenuation of virulence in the vaccine candidates, as well as their route and mode of administration, and to define the correlates of protection. In this study, we have compared three strains of Shigella flexneri 5--the wild-type M90T, an aroC mutant, and a double purE aroC mutant--for their pathogenicity, immunogenicity, and protective capacity. Protection against keratoconjunctivitis, induced by wild-type M90T, was used as the protection read out in guinea pigs that were inoculated either intranasally or intragastrically. Following intranasal immunization, the aroC mutant elicited weak nasal tissue destruction compared to M90T and achieved protection correlated with high levels of local anti-lipopolysaccharide immunoglobulin A (IgA), whereas the purE aroC double mutant, which also elicited weak tissue destruction, was not protective and elicited a low IgA response. Conversely, following intragastric immunization, only the M90T purE aroC double mutant elicited protection compared to both the aroC mutant and the wild-type strain. This mutant caused mild inflammatory destruction, particularly at the level of Peyer's patches, but it persisted much longer within the tissues. This could represent an essential parameter of the protective response that, in this case, did not clearly correlate with high anti-lipopolysaccharide IgA titers.

Phenotypic and genotypic characterization of Vibrio cholerae isolates from a recent cholera outbreak in Senegal: comparison with isolates from Guinea-Bissau.

A total of 127 strains of Vibrio cholerae (117 V. cholerae O1 and 10 nonagglutinating strains) isolated from a recent cholera outbreak in Senegal and four strains isolated in Guinea-Bissau (during the survey of a cholera epidemic that occurred 10 months before the Senegalese one) were analyzed. Strains were characterized by conventional methods (biochemical and serologic identification, susceptibility to antimicrobial agents), polymerase chain reaction for genes encoding cholera toxin (CtxA), zonula occludens toxin (Zot), and accessory cholera enterotoxin (Ace), and by ribotyping. Conventional methods showed that all strains of V. cholerae O1 belonged to serotype Ogawa, biotype El Tor and were resistant to the vibriostatic agent O129 (2,4-diamino 6,7-diisopropylpteridine phosphate), cotrimoxazole, and chloramphenicol; all strains were sensitive to tetracycline, a drug that has been extensively used in cholera therapy. Most of these V. cholerae O1 (112 strains from Senegal and four strains from Guinea-Bissau) had an intact core region (virulence cassette) and amplified a 564-basepair (bp) fragment of ctxA, a 1083-bp fragment of zot, and a 314-bp fragment of ace. Ribotyping of V. cholerae O1 strains after Bgl I restriction of total DNA revealed that ribotype B5a, which is the predominant ribotype of this seventh pandemic of cholera, was not isolated. Instead, a new ribotype was identified and designated B27 in our data bank. Since O1 isolates from Guinea-Bissau and Senegal have the same biotype, serotype, and ribotype and as the Guinea-Bissau outbreak that preceded the one in Senegal, this emerging ribotype probably came from Guinea-Bissau. Nonagglutinating strains exhibited no resistance to the O129 agent and to the tested antibiotics, they were all negative for virulence cassette, except for one strain with the ctxA and zot genes isolated from a patient with diarrhea, and there was a great variability of ribotypes among these strains. There was no difference between environmental O1 strains isolated from water and strains isolated from patients with cholera, suggesting that fecally contaminated water is an important reservoir for infection.

[Bacterial, viral and parasitic etiologies of acute infantile diarrhea in a rural Senegal]. / Etiologies bactériennes, virales et parasitaires des diarrhées aigües infantiles en zone rurale sénégalaise.

We have studied the incidence of parasites, viruses and bacteria associated with acute infantile diarrhea in rural Senegal. Among parasitoses, Cryptosporidium parvum (7.7%) is the most frequent, followed by Entamoeba histolytica (5.1%). The first bacteriological etiologic agent is Escherichia coli (20.9%). Rotavirus are also frequently isolated (14.7%). Prevalence of pathogens is higher: among children over 6 months and under two years old, among children either with mixed feeding or weaned, during the raining season, except for rotaviruses. Breast feeding seems to be a good protective factor against bacterial and parasitological infections but not against rotavirus contaminations.

[Bacterial etiologies of acute infantile diarrhea in Dakar]. / Etiologies bactériennes des diarrhées aiguës infantiles à Dakar.

Systematic research into all the bacterial etiological agents responsible for acute diarrhoea was undertaken on 276 diarrhoea stools collected from children aged 0-5 years. Particular attention was given to finding bacterial agents usually overlooked during routine checks: Campylobacter, Vibrionaceae and Yersinia enterocolitica.

[Campylobacter pylori and the gastric mucosa. Apropos of the detection of Campylobacter pylori in 12 patients with gastric mucosa lesions]. / Campylobacter pylori et muqueuse gastrique. A propos de la mise en évidence de Campylobacter pylori chez 12 patients porteurs de lésions muqueuses gastriques.

The authors report the results of systematic research on Campylobacter pylori during high endoscopy. Of the 60 patients examined, 12 were found to have the germ in their antral, gastric mucosa. All these patients had a history of chronic gastritis. They recall the role of this germ in creating chronic gastritis, and evoke the hypothesis that the mucosa becomes fragile facilitating the appearance of an ulcer.

[Incidence of pathogenic Escherichia coli in acute infantile diarrhea in Dakar]. / Incidence des Escherichia coli pathogènes sur les diarrhées aiguës infantiles à Dakar.

We have studied the incidence of enteropathogenic (EPEC), enteroinvasive (EIEC) and enterotoxigenic (ETEC) Escherichia coli associated with infant acute diarrhoeal disease in Dakar during a period of one year. We report 405 strains of Escherichia coli suspected to be the etiologic agent of the diarrhoea and isolated from 405 diarrheic stools of 0-5 years old children. We have isolated 119 pathogenic Escherichia coli with 63 EPEC (15.5%), 3 ETEC (0.7%) and 53 ETEC (13.1%) including 23 strains releasing heat-labile enterotoxin (LT+) and 30 strains releasing heat-stable enterotoxin (ST+). No ST+/LT+ strain was isolated. Escherichia coli with colonization factor antigens were isolated from 62 children. Almost all of them are CFAI+. Only one strain is CFAII+ and another one agglutinates with both CFAI and CFAII antisera. Among these CFA+ strains 5 belong to the EPEC group, 29 are enterotoxigenic (25 ST+ and 4 LT+) and 28 do not belong to any known etiopathologic group. Near 70% of the pathogenic Escherichia coli are from infants less than one year old, with a highest frequency between 7 and 12 months. Prevalence of ETEC is higher during the raining season. The existence of a great number of strains that belong to none of the 3 groups of etiopathologic Escherichia coli emphasis the need to search other factors of pathogenicity.