Aims:  The aims of this study were to evaluate the host‐specific distribution of Bacteroidales 16S rRNA gene sequences from human‐ and animal‐related effluents and faeces, and to define a ruminant‐specific marker. Methods and Results:  Bacteroidales 16S rRNA gene clone libraries were constructed from samples of effluent (sewage, bovine manure and pig slurry) and faeces (human, bovine, pig and wild bird), using PCR primers targeting order Bacteroidales. The phylogenetic analysis revealed six main distinct human‐, bovine‐, pig‐ and wild bird‐specific clusters. From the bovine‐specific cluster II, we designed a ruminant‐specific marker, Rum‐2‐Bac, and this showed 97% sensitivity (n = 30) and 100% specificity (n = 40) when tested by TaqMan® real‐time PCR. Average concentrations of this marker in bovine and sheep faeces and in bovine manure were 8·2 ± 0·5, 8·4 ± 1·3 and 7 ± 0·5 log10 copies per gram, respectively. It was also quantified in samples of runoff water impacted by bovine manure, with average concentrations of 5·1 ± 0·3 log10 copies per millilitre water. Conclusions:  Our results confirmed that some members of Bacteroidales isolated from effluents and faeces had host‐specific distributions. Identification of a bovine‐specific cluster made it possible to design a reliable ruminant‐specific marker. Significance and Impact of the Study:  The host‐specific distribution of Bacteroidales sequences from effluents mirrored the host‐specific distribution of sequences observed in individual faeces. This efficient new ruminant‐specific Bacteroidales 16S rRNA marker represents a useful addition to the microbial source tracking toolbox.

Background and Purpose: Diarrhoeagenic E. coli (DEC) is one of the germs responsible for childhood diarrhea in developing countries. This study aims at determining the prevalence of the five main pathotypes of DEC isolated from faeces of children under five years old with diarrhea or not, living in the city of Koula-Moutou. Methodology: Isolates of E. coli were phenotypically screened on chromID TM agar and molecularly by multiplex PCR to detect the presence of enteroaggregative E. coli (EAEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enterohemorragic E. coli (EHEC) and enteroinvasive E. coli (EIEC). The evaluation of their sensitivity to 12 β-lactam antibiotic molecules was carried out by Kirby Bauer method. This method has also made it possible to characterize phenotypically the different β-lactamases produced. Results and Conclusion: Overall, at least one DEC pathovar was detected in the 63 E. coli strains with phenotypic and molecular frequencies of 63.5% and 68.5% respectively. Thus, ETEC (28.3%) and EHEC (28.3%) were the most frequent DEC in diarrheal isolates. ETEC/EHEC hybrid was recorded in both groups with rates of 7.5% in diarrheal cases and 10.0% for controls. The results showed produced carbapenemase type β-lactamases

Objective: Colistin is one of the latest line of therapeutics used in the management of infections due to multiresistant Gram-negative bacteria. The current emergence of colistin resistance, in particular through the mediation of plasmid resistance genes (mcr1 and mcr2) in intestinal bacteria is a worldwide concern. The objective of this study is to evaluate the sensitivity of Salmonella and Shigella strains to colistin and the detection of mcr1 and mcr2 genes within these strains. Methodology and Results: The colistin sensitivity profile of 30 Salmonella strains and 5 Shigella strains was determined using the Minimum Inhibitory Concentrations in liquid medium of Mueller Hinton and the results were interpreted in accordance with the standards of the European Committee on Antimicrobial Susceptibility Testing Epidemiological cut-off 2020 version 10.0. Finally, the mcr1 and mcr2 genes were detected by a conventional PCR. Overall, a phenotypic resistance rate of 20% was recorded for Salmonella-Shigella pathogens, with a frequency of 17.1% for Salmonella and 2.9% for Shigella. Molecular screening of these isolates revealed a lack of detection of the mcr1 and mcr2 genes in their genetic heritage. Conclusion and application of results: this study shows that Salmonella and Shigella strains are resistant to colistin, however the mcr 1 and 2 genes have not been amplified. To this end, the rational use of colistin must be applied in the human and animal field in order to curb the increase and spread of resistance to this molecule. Keywords: Colistin, Gabon, mcr, resistance, Salmonella-Shigella

Wavé-fortex is a dietary supplement designed to Gabon, to fight against the problems of malnutrition and undernourishment. It would also contain diuretic properties, purgative, antimicrobial, aphrodisiac, influenza, European Scientific Journal November 2016 edition vol.12, No.33 ISSN: 1857 -7881 (Print) e -ISSN 1857 509 regulating blood pressure, reducing overweight and stimulating sperm production. This work was carried out to study the physicochemical and biochemical characteristics of this health food. The results revealed that Wavé-fortex was heavily dehydrated and contained 6.27% of crude ash and 11.32% of total gross fibers. The mineral level, Wavé-fortex contains 1.27% of calcium, 0.09% of iron, 0.37% of magnesium, 0.87% of potassium and 0.01% of zinc. Biochemical analyzes showed that this functional food contained 45.69% of carbohydrates, 26.01% of protein and 4.67% of fat. This gives it an energy value of 3.55 kcal / g of dry matter. Wavé-fortex is an acidic product (pH 4.02) with high levels of vitamin A (2.38%), vitamin C (1.93%) and phenolic compounds (11.83%). The different levels of these compounds are capable of validating the various nutritional properties attributed to this food powder.Keywords: Nutritional supplement; malnutrition; mineral elements; vitamins; Energy; Therapy. RésuméWavé-fortex est un complément alimentaire conçu au Gabon, pour lutter contre les problèmes de malnutrition et de sous alimentation. Il contiendrait également des propriétés diurétique, purgative, antimicrobienne, aphrodisiaque, antigrippale, régulatrice de la pression artérielle, réductrice de la surcharge pondérale, et stimulatrice de production des spermatozoïdes. Le présent travail a été réalisé pour étudier les caractéristiques physicochimiques et biochimiques de cet alicament. Les résultats obtenus ont révélé que Wavé-fortex était fortement déshydraté et contenait 6,27% de cendres brutes et 11,32% de fibres brutes totales. Au niveau minéral, Wavé-fortex contient 1,27% de Calcium, 0,09% de Fer, 0,37% de magnésium, 0,87% de potassium et 0,01% de zinc. Les analyses biochimiques ont montré que cet alicament renfermait 45,69% de glucides, 26,01% de protéines et 4,67% de lipides. Ce qui lui donne une valeur énergétique de 3,55 Kcal/g de matière sèche. Wavé-fortex est un produit acide (pH 4,02) avec de fortes teneurs en vitamines A (2,38%), vitamine C (1,93%) et en composés phénoliques (11,83%). Les différentes teneurs de ces composés sont de nature à valider les diverses propriétés nutritives attribuées à cette poudre alimentaire.

Background Better knowledge of endogenous germs and their associated demographic and environmental risk factors in a locality are essential to treat childhood diarrheal diseases. The aim of the study was to identify and characterize bacterial and parasitic pathogens responsible for childhood diarrhea, and to identify environmental risk factors associated with diarrhea in children under 5 years old living in Koula-Moutou, East-Central Gabon. Methods A cross-sectional study was performed from May 2016 to February 2018. One-hundred and thirty-two (132) children under 5 years old were enrolled. The detection of pathogens in stool samples was performed using microscopic examination and MIF concentration for parasites, and conventional culture on selective media for enterobacteria. Results The prevalence of diarrheal pathogens was 46.1%, including bacterial enteropathogens (25.5%) and parasites (20.6%). A total of 228 pathogenic organisms were isolated, including 199 bacterial strains (87.3%) and 29 parasites (12.7%). The specific richness of the isolated enterobacteria was 24 species with a high prevalence of E. coli (39.8%), including 26.7% for the diarrheal cases and 13.1% for the controls. Twelve (12) parasite species were also isolated and the most common types of parasites were rhizopods (44.8%), which accounted for 37.9% of the diarrheal cases and 6.9% of the controls. Univariate analysis showed that the presence of watercourses (OR = 3.37) and domestic animals (OR = 1.65) were significant risk factors for diarrhea. Conclusion The findings show a high prevalence of bacterial enteropathogens but a low rate of parasites and bacteria-parasite co-infection in the study area. Risk factors associated with diarrhea among children under 5 years old were the presence of watercourses and domestic animals. These findings highlight the need to strengthen the routine examination of diarrheic stool samples for the diagnosis of pathogenic organisms. Further analyses are required to better understand the etiologies and risk factors associated with the transmission of bacteria and parasites in rural, semi-urban and urban regions of Gabon.