Genetic Diversity of Simulium damnosum complex Onchocerciasis Vector and its Influence on Entomological Monitoring in the West of Côte d'Ivoire

In West Africa, Onchocerca volvulus, the causative pathogen of human onchocerciasis, is transmitted by sibling species of the Simulium damnosum complex. Little is known about blackfly intraspecific variability and its consequences on vectorial capacity in Côte d’Ivoire. This study reports the use of microsatellite markers to study the genetic profile and evaluate the gene flow between populations of S. damnosum s.l from three (3) different epidemiological facies in western Côte d’Ivoire, fifteen years after the end of onchocerciasis control program. Adult flies were collected on human attractants from 07 : 00 to 18 : 00 hours for three consecutive days by site, from December 2016 to October 2017. Four (4) microsatellite loci were used to characterize individuals from these populations. The four (4) loci were polymorphic with 13.25 alleles per locus. Two (2) specific alleles (190 bp and 290 bp), were reveal abundant with respective frequencies of 0.46 % and 0.58 %. Asignificant heterozygosity deficiency and low genetic differentiation (FST = 0.046, P = 0.024) have been observed for all the populations. The genetic analysis showed significant deviation from Hardy-Weinberg and significant heterozygosity deficiencies. Then, the great interspecific variability would be a general characteristic in S. damnosum s.l. At last, a probable evolution of the invasive strains of S. damnosum would have occurred in these localities. This study has shown significant deviation from Hardy-Weinberg and significant heterozygosity deficiencies in the populations of the three localities. The loci give independent estimate genetic parameters. The H3-4 locus to a low genetic differentiation between the populations. &nbsp

Évaluation de la diversité et de la charge parasitaire des lacs de la ville de Yamoussoukro en Côte d’Ivoire

Objectif: Cette étude vise à caractériser les parasites des eaux des lacs de Yamoussoukro et d’étudier les risques sanitaires dans la réutilisation de ces eaux usées afin d'en tirer les conséquences épidémiologiques.Méthodologie et résultats : Vingt-huit échantillons d’eaux résiduaires ont été collectés dans huit lacs de Yamoussoukro à partir de récipients stériles. La méthode de Bailenger a été utilisée pour la mise en évidence des parasites. La reconnaissance spécifique et le dénombrement des parasites ont été faits à l’aide d’un microscope optique. Les prévalences observées ont été comparées entre lacs et par espèce de parasite.Au total, 13 espèces de parasites: Ankylostoma sp., Strongyloïde sp., Ascaris sp., Nematodirus sp., Trichuris sp., Toxocara sp., Capillaria sp., Ascaridia galli, Enterobius vermicularis, Taenia sp., Hymenolepis diminuta., Entamoeba coli., Entamoeba histolytica et les larves de Strongles ont été détectées dans les eaux des huit lacs investigués à Yamoussoukro. Les oeufs d’helminthes sont quasi-présents dans tous les lacs investigués avec des charges parasitaires variables. Trois espèces ont donné des charges parasitaires très élevées : L’espèce Ankylostoma sp a été retrouvée dans tous les lacs. Les Strongyloïdes et les Ascaris sp présentaient des prévalences de 100 % et 87,5 % respectivement. Au niveau des lacs investigués, lacs, le lac N° 5 était le plus parasité avec une prévalence de 100 % sur l’ensemble des parasites, ensuite viennent les lacs N°1, 6 et 8 (69,2 %) puis les lacs G0, 9 et 10 (53,8 %).Conclusion et application des résultats: Les analyses parasitologiques montrent que les lacs de Yamoussoukro sont contaminés par des parasites d’importances médicales. L’infestation de ces eaux en agents pathogènes interdit leur usage en agriculture ce qui n’est pas couramment observé sur le terrain.Mots clés: Parasites, lacs, eaux résiduaires, Yamoussoukro, Côte d’IvoireEnglish AbstractObjectives: Water, source of life is essential for all living beings. After its use, the water is loaded in various elements modifying its physical, chemical and biological characteristics. One of the most serious environmental problems is the problem of sanitation. Indeed, human activity leads to the production of wastewater discharged daily into the wild.Methodology and results: Twenty-eight waste water samples were collected from eight Yamoussoukro lakes from sterile containers. The method of Bailenger was used for the detection of parasites. The specific recognition and enumeration of the parasites was done using an optical microscope Prevalences observed were compared between lakes and by parasite species. A total of 13 species of parasites: Ankylostoma sp., Strongyloïd sp., Ascaris sp., Nematodirus sp., Trichuris sp., Toxocara sp., Capillaria sp., Ascaridia galli, Enterobius vermicularis, Taenia sp., Hymenolepis diminuta., Entamoeba coli., Entamoeba histolytica et les larves de Strongles were detected in the waters of Yamoussoukro lakes. Helminth eggs are almost present in all investigated lakes with variable parasite loads. Three species gave very high parasite loads: The species Ankylostoma sp was found in all lakes. Strongyloids and Ascaris sp had prevalence rates of 100 % and 87.5 %, respectively. At the level of the parasite load of the lakes, Lake N ° 5 was the most parasitized with a prevalence of 100 % on all the parasites, then the lakes N ° 1, 6 and 8 (69,2 %) then the Lakes G0, 9 and 10 (53.8 %).Conclusion and application of results: Parasitological analysis show that Yamoussoukro lakes are contaminated by parasites of medical importance. The infestation of these waters with pathogens prohibits their use in agriculture, which is not commonly observed in the field.Keywords: Parasites, lakes, wastewater, Yamoussoukro, Côte d’Ivoir

Microbiological and physico-chemical characterisation of well water in the town of Korhogo, Côte d’Ivoire

Water is essential to the life of every living organism. The water used by the consumer must be safe for the preservation of his health. The objective of this study was to assess the quality of well water used in households in the city of Korhogo. To do this, water samples were taken from the wells of different households. Parameters such as pH, temperature, electrical conductivity and total dissolved solids were measured at the sampling sites. Nitrates and ammonium were determined by spectrophotometric methods using sodium salicylate and indophenol blue, respectively. The membrane filtration technique has been used for the enumeration of total coliforms, Escherichia coli, fecal enterococci, sulfite-reducing anaerobic bacteria, yeasts and moulds. The agar incorporation method was used for the enumeration of mesophilic aerobic germs. The non-conformity relative to pH was 73%. All wells were contaminated with nitrates and ammonium. Non-compliance rates of 80% and 53% were obtained for nitrates and ammonium respectively. Non-compliance with mesophilic aerobic germs, total coliforms, E. coli and fecal enterococci was 100% for each indicator. No spore of sulphite-reducing clostridia has been identified. Contamination rates of 80% (mould) and 67% (yeast) were recorded. The moulds isolated from the various water samples belong to the genus Aspergillus. The quality of well water in households is not suitable for human consumption. These waters require treatment or household residents must switch to other safe sources of drinking water

Prevalence of Virulence Genes Associated with Diarrheagenic Pathotypes of Escherichia coli

This study was conducted to characterize virulence genes of Escherichia coli isolates from water, sediment, fish, and crab in Aby Lagoon. Serogrouping was performed by EPEC antisera in 113 E. coli strains. The presence of diarrhea-associated genes (eae, stx, AggR, elt, and est) was assessed by multiplex PCR using specific primers. Based on the multiplex PCR, sixty-two isolates (42 from water, 19 from sediment, and 1 from crab) were positive for virulence genes, including 34 positive for elt (ETEC), 46 positive for est (ETEC), 24 positive for both elt and est, 6 positive for stx (EHEC), 1 positive for both stx + est, and 1 positive for both stx + elt. Genes eae (EPEC) and AggR (EAEC) were not detected. Nine serogroups (O114, O127, O55, O111, O86, O119, O126, O128, and O142) were identified. This study revealed the presence of diarrheagenic and nondiarrheagenic E. coli and potential public health risks if fishery products are not appropriately cooked

Prevalence and Intensity of Intestinal Parasites and Malaria in Pregnant Women at Abobo District in Abidjan, Côte d’Ivoire

A prospective study was carried out from 2010 to 2012 at the Hôpital Général d’Abobo (HGA) in Abidjan, in order to determine the impact of infectious and parasitic diseases on child cognitive development. Blood samples were examined by means of drop thick and blood smear, as for stool by direct examination and concentration by formalin-ether method. We evaluated the prevalence and the parasite load of malaria and gastrointestinal parasites and then investigated the risk factors for these disorders. Overall, 331 pregnant women in the last trimester of their pregnancy were enrolled. The plasmodic index was 3.9% with an infestation specific rate for P. falciparum of 100%. Concerning digestive protozoa, it has been observed 71.3% of nonpathogenic, against 9.7% of pathogens, either an overall prevalence of 51.4% of digestive parasites. The calculated average parasitic loads revealed 3089.2 tpz/μl of blood (95% CI, 591.1–5587.3) for malaria, 6.5 eggs per gram of stool (95% CI, 0.4–13.4) for intestinal helminths, and one (1) parasite by microscopic field for protozoa (common infestation). It has been shown that the occurrence of malaria has been linked to the nonuse of impregnated mosquito nets (χ2 = 0.012, p = 0.018) to age. No link could be established between the presence of digestive parasites and the age of pregnant women or socioeconomic conditions (level of education, profession, type of toilet). Malaria is less common in pregnant women, while the rate of digestive parasites remains high

Mise En Évidence De Nouvelles Structures Géologiques Dans La Région De Brobo (Centre De La Côte d’Ivoire). Aide À La Compréhension De La Tectonique Du Paléoprotérozoïque Du Craton Ouest Africain

The lithological and structural observations of the region of Brobo (Central Côte d'Ivoire) indicate a succession of metasedimentary rocks (micaschists with cordierite, silstones, graphitic sediments, sandstones with amphibole-garnet, etc.) intermixed with volcanic rocks (rhyolite, dacite, andesite, basalt and the volcanoclastics). The whole is intruded by granites with one or two micas, sometimes porphyries, granodiorites, gabbros, and granite gneisses. Interpretations of Landsat ETM+ , RadarSat-1 and SRTM remote sensing imageries, as well as field data, revealed several lineament directions which, after field control, correspond to major faults and shear zones. These large structures show the N-S, NE-SW, NNE-SSW, E-W, NWSE, and NNW-SSE orientations. The field data also made it possible to describe several structures and to propose a preliminary geodynamic model for the setting and structuring of the formations of this region. This model suggests that the geodynamic took place in three stages: distension with a deformation of basement formations generating a gneissocity (D1), as well as deposits of sediments in the basins; followed by a NW-SE to E-W convergence generating a cleavage in the volcanogenic series (D2). This phase of deformation continues while creating, locally, a strain slip cleavage or a transposed schistosity. The third cleavage affects the volcanogenic series (fractures cleavages, D3) and ends in large corridors of ductile shear zones and associated faults

Candidate genes-based investigation of susceptibility to Human African Trypanosomiasis in Cote d'Ivoire

Human African Trypanosomiasis (HAT) or sleeping sickness is a Neglected Tropical Disease. Long regarded as an invariably fatal disease, there is increasing evidence that infection by T. b. gambiense can result in a wide range of clinical outcomes, including latent infections, which are long lasting infections with no parasites detectable by microscopy. The determinants of this clinical diversity are not well understood but could be due in part to parasite or host genetic diversity in multiple genes, or their interactions. A candidate gene association study was conducted in Côte d’Ivoire using a case-control design which included a total of 233 subjects (100 active HAT cases, 100 controls and 33 latent infections). All three possible pairwise comparisons between the three phenotypes were tested using 96 SNPs in16 candidate genes (IL1, IL4, IL4R, IL6, IL8, IL10, IL12, IL12R, TNFA, INFG, MIF, APOL1, HPR, CFH, HLA-A and HLA-G). Data from 77 SNPs passed quality control. There were suggestive associations at three loci in IL6 and TNFA in the comparison between active cases and controls, one SNP in each of APOL1, MIF and IL6 in the comparison between latent infections and active cases and seven SNP in IL4, HLA-G and TNFA between latent infections and controls. No associations remained significant after Bonferroni correction, but the Benjamini Hochberg false discovery rate test indicated that there were strong probabilities that at least some of the associations were genuine. The excess of associations with latent infections despite the small number of samples available suggests that these subjects form a distinct genetic cluster different from active HAT cases and controls, although no clustering by phenotype was observed by principle component analysis. This underlines the complexity of the interactions existing between host genetic polymorphisms and parasite diversity

Latex Micro Diagnosis, Modern Management Tool of Rubber Plantations of Clones With Active or Rapid Metabolism IRCA 18, IRCA 130, PB 235, PB 260 and PB 330

The cultivated rubber clones are sensitive to latex harvesting regimes according to their laticiferous metabolism. Thus, in order to determine the best latex harvesting systems of clones with active or rapid metabolism (IRCA 18, IRCA 130, PB 235, PB 260 and PB 330), six latex harvesting technologies are applied to them in a bulk statistical device from Fisher to four rehearsals. The rubber is tapped in downward half spiral stimulated or not for nine years after the opening of the tapping panel. The agronomic parameters (production, vegetative growth), the tapping panel dryness and those of the latex micro diagnosis were evaluated. The results indicate that these clones independently of the latex harvesting system have good rubber productivity (2310 kg.ha -1.y1) with good radial vegetative growth (2.9 cm.y-1). Their trees show a wellbalanced physiological profile and an acceptable sensitivity to the tapping panel dryness (4.9%). However, the physiological index, the bark consumption and the sensitivity to the tapping panel dryness lead to retain the latex harvesting technologies “ S/2 d3 6d/7 Pa1(1) ET2.5% 4/y and S/2 d4 6d/7 Pa1(1) ET2.5% 4/y ” for the best. This index, favorably influencing the choice of technologies adapted to clones with active metabolism, contributes to the modern and efficient management of a rubber plantation