Caractérisation physico-chimique et bactériologique des eaux usées brutes du réseau d’égout de la ville d’Abidjan

La gestion des eaux résiduaires urbaines pose de nombreux problèmes environnementaux qui deviennent préoccupants pour la santé des populations d’Abidjan. Pour remédier à cela, il est souhaitable de mettre en place des stations d’épurations. Ainsi, notre étude se présente comme une étude préliminaire visant à caractériser sur le plan physico-chimique et bactériologique les effluents du réseau d’égout de la ville d’Abidjan. Pour ce faire, nous avons effectué six campagnes de  prélèvement d’eaux usées durant une  année (Décembre 2013-Novembre 2014) sur huit (8) sites spécifiques du réseau d’égout. Ces échantillons ont fait l’objet  d’analyses physico-chimiques et bactériologiques sur la base des normes Françaises, Canadiennes et celles décrites par Rodier. Les résultats obtenus indiquent qu’à l’exception du phosphore total (PT) dont les concentrations sont comprises entre 4,3±4 et 10,9±6,7mg/l, les autres principaux indicateurs de pollution que sont l’azote total (NTK, 73,3±32 à 118,2±37,6 mg/l), les matières en suspension (MES, 79±23,3 à325,2±270,3 mg/l), la demande biochimique en oxygène en 5 jours (DBO5, 127,3±87,7 à 863,7±262,2 mgO2/l) et la demande chimique en oxygène (DCO, 276,2±195,6 à 975,3±249,4 mgO2/l) sont au-delà des valeurs guidesrecommandées par l’Etat de Côte d’Ivoire à travers le service d’inspection des installations classées (SIIC) en matière de rejet des effluents en milieu récepteur. L’analyse de la flore bactérienne des effluents révèle que les concentrations de coliformes fécaux et les streptocoques fécaux excèdent les valeurs indicatives préconisées par l’OMS.Mots clés : Caractérisation, eaux usées, réseau d’égout, bactériologie, physico-chimie

Update on the current status of onchocerciasis in Cote d’Ivoire following 40 years of intervention: Progress and challenges

Background Onchocerciasis control in Côte d’Ivoire started with aerial insecticide spraying in 1974 and continued with community directed treatment with ivermectin (CDTi) from 1992 to the present. Onchocerciasis and lymphatic filariasis (LF) are co-endemic in 46 of the 81 health districts in the country. Fourteen and 12 districts are endemic for only LF or onchocerciasis, respectively. This paper aims to review the impact of past interventions on onchocerciasis in Côte d’Ivoire between 1975 and 2013, and review plans for disease elimination. Methods We reviewed microfilaria (MF, skin snip) prevalence and community microfilarial load (CMFL) data from published reports from 53 health districts during two major epidemiological assessment periods. Data from 1975 through 1991 provided information on the impact of vector control, and data from 1992 through 2016 provided information on the impact of CDTi. Results Weekly aerial insecticide spraying in 8 endemic districts between 1975 and 1991 reduced the overall MF prevalence by 68.1% from 43.5% to 13.9%. The CMFL also decreased in 7 out of 8 surveyed communities by 95.2% from 9.24 MF/snip to 0.44 MF/snip. Ivermectin distribution started in 1992. The coverage targets for control (65% of the total population) was reached in most endemic districts, and some areas achieved 80% coverage. Two sets of surveys were conducted to assess the impact of CDTi. Results from the first repeat surveys showed a significant decrease in overall MF prevalence (by 75.7%, from 41.6% to 10.1%). The second follow-up evaluation showed further improvement in most endemic districts and also documented major reductions in CMFL compared to baseline. Conclusions Extensive data collected over many years document the very significant impact of interventions conducted by the National Onchocerciasis and other Eyes Diseases Control Programme during challenging times with periods of civil unrest. The Health Ministry has now integrated efforts to control neglected tropical diseases and adopted the goal of onchocerciasis elimination

Pharmacokinetics, safety, and efficacy of a single co-administered dose of diethylcarbamazine, albendazole and ivermectin in adults with and without Wuchereria bancrofti infection in Cote d\u27Ivoire

BackgroundA single co-administered dose of ivermectin (IVM) plus diethylcarbamazine (DEC) plus albendazole (ALB), or triple-drug therapy, was recently found to be more effective for clearing microfilariae (Mf) than standard DEC plus ALB currently used for mass drug administration programs for lymphatic filariasis (LF) outside of sub-Saharan Africa. Triple-drug therapy has not been previously tested in LF-uninfected individuals from Africa. This study evaluated the pharmacokinetics (PK), safety, and efficacy of triple-drug therapy in people with and without Wuchereria bancrofti infection in West Africa.MethodsIn this open-label cohort study, treatment-naïve microfilaremic (>50 mf/mL, n = 32) and uninfected (circulating filarial antigen negative, n = 24) adults residing in Agboville district, Côte d’Ivoire, were treated with a single dose of IVM plus DEC plus ALB, and evaluated for adverse events (AEs) until 7 days post treatment. Drug levels were assessed by liquid chromatography and mass spectrometry. Persons responsible for assessing AEs were blinded to participants’ infection status.FindingsThere was no difference in AUC0-inf or Cmax between LF-infected and uninfected participants (P>0.05 for all comparisons). All subjects experienced mild AEs; 28% and 25% of infected and uninfected participants experienced grade 2 AEs, respectively. There were no severe or serious adverse events. Only fever (16 of 32 versus 4 of 24, PConclusionsModerate to heavy W. bancrofti infection did not affect PK parameters for IVM, DEC or ALB following a single co-administered dose of these drugs compared to uninfected individuals. The drugs were well tolerated. This study confirmed the efficacy of the triple-drug therapy for clearing W. bancrofti Mf and has added important information to support the use of this regimen in LF elimination programs in areas of Africa without co-endemic onchocerciasis or loiasis.Trial registrationClinicalTrials.gov NCT02845713.</div

Contamination du lait caillé et de l’oeuf consommé en Côte d’Ivoire par des pesticides organochlorés

La présente étude vise à évaluer l’aspect sanitaire de l’alimentation humaine à travers deux produits à forte consommation en Côte d’Ivoire : le lait caillé et l’oeuf. Ainsi, 30 échantillons de lait caillé ont été achetés et 30 échantillons d’oeufs de poulet ont été collectés dans trois fermes dans la ville d’Abidjan. Ces échantillons ont été traités dans le but de déterminer les résidus de 12 POC (Pesticides OrganoChlorés). Les analyses ont été réalisées au CG sur colonne capillaire avec un détecteur à capture d'électrons. Les résultats observés révèlent une contamination du lait caillé et de l’oeuf par 5 POC. Ainsi, des charges moyennes en μg/kg des isomères hexachlorocyclohexane (HCH) allant de 0,125 à 0,997 et de 1,870 à 35,907, de l’endosulfan allant de 0,045 à 0,563 et non détecté, de la dieldrine allant de 0,025 à 0,263 et de 5,727 à 69,710 et du Dichlorodiphenyltrichloroethane (DDT) et métabolites allant de 0,133 à 0,813 et de 21,105 à 75,22, ont été respectivement déterminées dans le lait caillé et dans l’oeuf. La teneur résiduelle moyenne des isomères HCH, des cyclodiènes (dieldrine, et endosulfane) et du DDT et ses métabolites constituent respectivement 40%, 40% et 20% de la moyenne du total des POC mesurés dans le lait caillé et respectivement 20%, 20% et 60% de celle mesurée dans l’oeuf.Mots-clés: pesticides organochlorés, lait caillé, oeuf, Côte d’Ivoire. Contamination of the curdled milk and the egg consumed in Ivory Coast by organochlorinated pesticides This study aims to determine the levels of organochlorinated pesticides (OCPs) in the curdled milk and egg. Thus, 30 samples of curdled milk were purchased and 30 egg samples were collected from three farms in the area of the lagoons. These samples were processed in order to determine the residues 12 OCPs. Analyses were performed by GC capillary column with electron capture detector. The observed results indicate contamination of curdled milk and egg by 5 OCPs. Thus, average loads in μg/kg of hexachlorocyclohexane (HCH) isomers ranging from 0.125 to 0.997 and 1.870 to 35.907, endosulfan ranging from 0.045 to 0.563 and undetected, dieldrin ranging from 0.025 to 0.263 and 5.727 to 69.710 and dichlorodiphenyltrichloroethane (DDT) and metabolites ranging from 0.133 to 0.813 and 21, 105 to 75.22, respectively, were determined in the curdled milk and egg. The average residual HCH isomers, cyclodiene (dieldrin and endosulfan) and DDT and its metabolites is respectively 40%, 40% and 20% of the average total OCPs measured in curdled milk and respectively 20%, 20 % and 60% of that measured in the bud.Keywords: organochlorinated pesticides, curdled milk, egg, Ivory Coast

Systems analysis-based assessment of post-treatment adverse events in lymphatic filariasis

BACKGROUND:Lymphatic filariasis (LF) is a neglected tropical disease, and the Global Program to Eliminate LF delivers mass drug administration (MDA) to 500 million people every year. Adverse events (AEs) are common after LF treatment. METHODOLOGY/PRINCIPAL FINDINGS:To better understand the pathogenesis of AEs, we studied LF-patients from a treatment trial. Plasma levels of many filarial antigens increased post-treatment in individuals with AEs, and this is consistent with parasite death. Circulating immune complexes were not elevated in these participants, and the classical complement cascade was not activated. Multiple cytokines increased after treatment in persons with AEs. A transcriptomic analysis was performed for nine individuals with moderate systemic AEs and nine matched controls. Differential gene expression analysis identified a significant transcriptional signature associated with post-treatment AEs; 744 genes were upregulated. The transcriptional signature was enriched for TLR and NF-κB signaling. Increased expression of seven out of the top eight genes upregulated in persons with AEs were validated by qRT-PCR, including TLR2. CONCLUSIONS/SIGNIFICANCE:This is the first global study of changes in gene expression associated with AEs after treatment of lymphatic filariasis. Changes in cytokines were consistent with prior studies and with the RNAseq data. These results suggest that Wolbachia lipoprotein is involved in AE development, because it activates TLR2-TLR6 and downstream NF-κB. Additionally, LPS Binding Protein (LBP, which shuttles lipoproteins to TLR2) increased post-treatment in individuals with AEs. Improved understanding of the pathogenesis of AEs may lead to improved management, increased MDA compliance, and accelerated LF elimination

Effectiveness of community-based burden estimation to achieve elimination of lymphatic filariasis: A comparative cross-sectional investigation in Côte d’Ivoire

For lymphatic filariasis (LF) elimination, endemic countries must document the burden of LF morbidity (LFM). Community-based screening (CBS) is used to collect morbidity data, but evidence demonstrating its reliability is limited. Recent pilots of CBS for LFM alongside mass drug administration (MDA) in Côte d’Ivoire suggested low LFM prevalence (2.1–2.2 per 10,000). We estimated LFM prevalence in Bongouanou District, Côte d’Ivoire, using a comparative cross-sectional design. We compared CBS implemented independently of MDA, adapted from existing Ministry of Health protocols, to a population-based prevalence survey led by formally trained nurses. We evaluated the reliability of case identification, coverage, equity, and cost of CBS. CBS identified 87.4 cases of LFM per 10,000; the survey identified 47.5 (39.4–56.3; prevalence ratio [PR] 1.84; 95% CI 1.64–2.07). CBS identified 39.7 cases of suspect lymphoedema per 10,000; the survey confirmed 35.1 (29.2–41.5) filarial lymphoedema cases per 10,000 (PR 1.13 [0.98–1.31]). CBS identified 96.5 scrotal swellings per 10,000; the survey found 91.3 (83.2–99.8; PR 1.06 [0.93–1.21]); including 33.9 (27.7–38.8) filarial hydrocoele per 10,000 (PR of suspect to confirmed hydrocele 2.93 [2.46–3.55]). Positive predictive values for case identification through CBS were 65.0% (55.8–73.5%) for filarial lymphoedema; 93.7% (89.3–96.7%) for scrotal swellings; and 34.0% (27.3–41.2%) for filarial hydrocoele. Households of lower socioeconomic status and certain minority languages were at risk of exclusion. Direct financial costs were $0.17 per individual targeted and$69.62 per case confirmed. Our community-based approach to LFM burden estimation appears scalable and provided reliable prevalence estimates for LFM, scrotal swellings and LF-lymphoedema. The results represent a step-change improvement on CBS integrated with MDA, whilst remaining at programmatically feasible costs. Filarial hydrocoele cases were overestimated, attributable to the use of case definitions suitable for mass-screening by informal staff. Our findings are broadly applicable to countries aiming for LF elimination using CBS. The abstract is available in French in the S1 File.</jats:p

Translating preventive chemotherapy prevalence thresholds for Schistosoma mansoni from the Kato-Katz technique into the point-of-care circulating cathodic antigen diagnostic test

Background Intervention guidelines against Schistosoma mansoni are based on the Kato-Katz technique. However, Kato-Katz thick smears show low sensitivity, especially for light-intensity infections. The point-of-care circulating cathodic antigen (POC-CCA) is a promising rapid diagnostic test detecting antigen output of living worms in urine and results are reported as trace, 1+, 2+, and 3+. The use of POC-CCA for schistosomiasis mapping, control, and surveillance requires translation of the Kato-Katz prevalence thresholds into POC-CCA relative treatment cut-offs. Furthermore, the infection status of egg-negative but antigen-positive individuals and the intensity-dependent sensitivity of POC-CCA should be estimated to determine its suitability for verification of disease elimination efforts. Methodology We used data from settings in Africa and the Americas characterized by a wide range of S. mansoni endemicity. We estimated infection intensity-dependent sensitivity and specificity of each test at the unit of the individual, using a hierarchical Bayesian egg-count model that removes the need to define a ‘gold’ standard applied to data with multiple Kato-Katz thick smears and POC-CCA urine cassette tests. A simulation study was carried out based on the model estimates to assess the relation of the two diagnostic tests for different endemicity scenarios. Principal findings POC-CCA showed high specificity (> 95%), and high sensitivity (> 95%) for moderate and heavy infection intensities, and moderate sensitivity (> 75%) for light infection intensities, and even for egg-negative but antigen-positive infections. A 10% duplicate slide Kato-Katz thick smear prevalence corresponded to a 15–40% prevalence of ≥ trace-positive POC-CCA, and 10–20% prevalence of ≥ 1+ POC-CCA. The prevalence of ≥ 2+ POC-CCA corresponded directly to single slide Kato-Katz prevalence for all prevalence levels. Conclusions/significance The moderate sensitivity of POC-CCA, even for very light S. mansoni infections where the sensitivity of Kato-Katz is very low, and the identified relationship between Kato-Katz and POC-CCA prevalence thresholds render the latter diagnostic tool useful for surveillance and initial estimation of elimination of S. mansoni. For prevalence below 10% based on a duplicate slide Kato-Katz thick smear, we suggest using POC-CCA including trace results to evaluate treatment needs and propose new intervention thresholds that need to be validated in different settings

Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys

PURPOSE: Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys. METHODS: Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported. RESULTS: Between 29th February 2016 and 24th April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma. CONCLUSION: This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets

Influence of Masing damping on 1D site response using equivalent linear and non-linear methods

Despite significant developments in one-dimensional (1D) site response methods using non-linear (NL) analysis, the Equivalent Linear (EL) analysis remains the most widely used approach by practitioners to investigate the total stress response of a soil deposit. While the EL method is implemented using both shear modulus reduction curves and damping curves from laboratory test results, NL Cyclic Stress (CS) models are often computed so that they are consistent with the backbone stress-strain characteristics, but accept some inconsistencies in the energy dissipated by the hysteresis loops that are represented using a Masing’s rule approach. As such, EL analysis often provides a conservative site amplification factor and ground response spectrum, while NL models can lead to an over-damping of the ground response spectrum. This paper discusses the impact of discrepancies in these damping formulations on 1D site response using the EL model and a non-linear CS model computed in OpenSees. Traditional EL analysis is performed, as well as a modified EL approach that changes the original formulation in order to capture frequency-dependent soil stiffness and soil damping parameters that are consistent with the frequency content of the vertically propagating shear waves. While it is largely recognized that Masing behaviour introduces a bias in the site response at large strains, it has been found that a moderate strain pattern within the soil profile can also lead to a substantial under-prediction of the ground response