Estimating the burden of malaria in Senegal : Bayesian zero-inflated binomial geostatistical modeling of the MIS 2008 data

The Research Center for Human Development in Dakar (CRDH) with the technical assistance of ICF Macro and the National Malaria Control Programme (NMCP) conducted in 2008/2009 the Senegal Malaria Indicator Survey (SMIS), the first nationally representative household survey collecting parasitological data and malaria-related indicators. In this paper, we present spatially explicit parasitaemia risk estimates and number of infected children below 5 years. Geostatistical Zero-Inflated Binomial models (ZIB) were developed to take into account the large number of zero-prevalence survey locations (70%) in the data. Bayesian variable selection methods were incorporated within a geostatistical framework in order to choose the best set of environmental and climatic covariates associated with the parasitaemia risk. Model validation confirmed that the ZIB model had a better predictive ability than the standard Binomial analogue. Markov chain Monte Carlo (MCMC) methods were used for inference. Several insecticide treated nets (ITN) coverage indicators were calculated to assess the effectiveness of interventions. After adjusting for climatic and socio-economic factors, the presence of at least one ITN per every two household members and living in urban areas reduced the odds of parasitaemia by 86% and 81% respectively. Posterior estimates of the ORs related to the wealth index show a decreasing trend with the quintiles. Infection odds appear to be increasing with age. The population-adjusted prevalence ranges from 0.12% in Thille-Boubacar to 13.1% in Dabo. Tambacounda has the highest population-adjusted predicted prevalence (8.08%) whereas the region with the highest estimated number of infected children under the age of 5 years is Kolda (13940). The contemporary map and estimates of malaria burden identify the priority areas for future control interventions and provide baseline information for monitoring and evaluation. Zero-Inflated formulations are more appropriate in modeling sparse geostatistical survey data, expected to arise more frequently as malaria research is focused on eliminatio

Quality of Artesunate Tablets Sold in Pharmacies in Kumasi, Ghana

Purpose: The study was carried out to evaluate the quality of artesunate tablets sold in retail and wholesale pharmacies in Kumasi, Ghana. In particular, the study sought to ascertain the presence or otherwise of counterfeit artesunate tablets in Kumasi. Method: Artesunate tablets were purchased from pharmacies in Kumasi for the study. The mechanical properties of the tablets were evaluated, namely: uniformity of weight, breaking strength, friability and rate of disintegration in aqueous medium. Colorimetric methods were used to determine the presence of artesunate and to assay the tablets. Result: None of the artesunate tablets sampled was found to be a counterfeit. Most of the brands had acceptable mechanical properties in terms of mass uniformity, hardness, friability and disintegration time. However, the artesunate content of the tablets was variable (47.9-99.9 %). Six (35.3 %) of the samples passed the International Pharmacopoeia content uniformity test (93.7-99.9 %) while 11 (64.7 %) failed the test (47.9-89.4 %). However, only 3 (17.6 %) of the samples met the European Pharmacopoeia (Ph. Eur.) content requirements while 14 (82.4 %) failed to meet the requirements. Conclusion: The presence of substandard artesunate tablets on the Ghanaian market should alert drug regulatory authorities to be vigilant and continually monitor the quality of this life-saving drug. Keywords: Artesunate tablets, Artemisinins, Fast-red TR salt, Counterfeit drugs, Substandard drugs.Tropical Journal of Pharmaceutical Research Vol. 7(4) 2008: pp. 1179-118

Aménagements hydro-agricoles et santé (vallée du fleuve Sénégal)

Près de 1 500 personnes résidant dans les villages rattachés au périmètre irrigué MO 6bis (périmètre de Diomandou, département de Podor) ont fait l'objet de prélèvements d'urine et/ou de selle afin de déterminer la prévalence de la bilharziose urinaire, de la bilharziose intestinale ainsi que des autres parasitoses entériques. Chez les riverains du périmètre, 1 295 urines ont été examinées, parmi lesquelles sept contenaient des oeufs viables de #Schistosoma haematobium$, ce qui représente un taux de prévalence de 0,5$, ce qui correspond à un indice d'infestation de 0,1%. Il s'agissait là aussi d'un individu dont la contamination avait eu lieu en dehors de la zone d'étude. #Eschirichia coli$est la parasite entérique le plus répandu avec 17,2$, #Strongyloïdes stercoralis, #Ascaris lumbricoïdes et #Trichiuris trichiura$ sont rares et ne concernent qu'un peu moins de 2% des sujets examinés. Ces résultats démontrent l'absence, pour l'instant tout au moins, de foyers de transmission des bilharzioses dans les villages du périmètre de Diomandou. Le risque d'apparition de ces maladies est cependant important et dépend à la fois de l'évolution des infrastructures et de l'éventuelle apparition d'hôtes intermédiaires encore absent du réseau hydrographique de ce périmètre mis en place récemment. (Résumé d'auteur

The dynamics of a spatial data infrastructure– a national case study

It widely cited that 80% of government data is spatial in nature and the accessibility of this data is a critical aspect of E-government. Many countries are developing standardised infrastructures, which will allow sharing and reuse of spatial data. This paper presents the findings of a national level case study of the Spatial Data Infrastructure implementation in Ireland. The study draws on concepts from Corporate Information Infrastructure (CII), most notably the power of the installed base, role of standardisation, multiple actors and top-down versus bottom-up tensions. A significant outcome of this paper is the application of the CII concepts to a national level case study

Sex-dimorphic gene expression and ineffective dosage compensation of Z-linked genes in gastrulating chicken embryos

<p>Abstract</p> <p>Background</p> <p>Considerable progress has been made in our understanding of sex determination and dosage compensation mechanisms in model organisms such as <it>C. elegans</it>, <it>Drosophila </it>and <it>M. musculus</it>. Strikingly, the mechanism involved in sex determination and dosage compensation are very different among these three model organisms. Birds present yet another situation where the heterogametic sex is the female. Sex determination is still poorly understood in birds and few key determinants have so far been identified. In contrast to most other species, dosage compensation of bird sex chromosomal genes appears rather ineffective.</p> <p>Results</p> <p>By comparing microarrays from microdissected primitive streak from single chicken embryos, we identified a large number of genes differentially expressed between male and female embryos at a very early stage (Hamburger and Hamilton stage 4), long before any sexual differentiation occurs. Most of these genes are located on the Z chromosome, which indicates that dosage compensation is ineffective in early chicken embryos. Gene ontology analyses, using an enhanced annotation tool for Affymetrix probesets of the chicken genome developed in our laboratory (called Manteia), show that among these male-biased genes found on the Z chromosome, more than 20 genes play a role in sex differentiation.</p> <p>Conclusions</p> <p>These results corroborate previous studies demonstrating the rather inefficient dosage compensation for Z chromosome in birds and show that this sexual dimorphism in gene regulation is observed long before the onset of sexual differentiation. These data also suggest a potential role of non-compensated Z-linked genes in somatic sex differentiation in birds.</p

Sub-optimal pain control in patients with rheumatic disease.

The visual analog scale (VAS) of pain is a ubiquitous clinical and research tool with widespread application in the rheumatic diseases. The objectives of this study were to assess if patients report pain differently to doctors or nurses, to determine reproducibility of this test for diagnosis, age, gender, and treatment, and to ascertain the level of pain in patients attending general rheumatology clinics. Using a standardized line of exactly 100 mm and instructions with identical wording, consecutive patients attending general rheumatology clinics were asked to score their perceived level of pain in the preceding week. Two assessments were carried out, one before and one after the clinic visit, and each patient was questioned by both a doctor and a nurse. Differences between the first and second VAS scores (VAS1 and VAS2) were recorded. One hundred and eight patients completed the study (69 female). VAS1 and VAS2 scores were administered by a similar number of doctors and nurses. There was no significant difference between mean VAS1 and VAS2 scores (41.1 vs. 41.4 mm, p = 0.78). VAS1 and VAS2 differed by \u3c4 mm in\u3e59% of patients. Age, gender, or diagnosis did not influence VAS1 or VAS2. Differences in scores were independent of which health professional administered the scale (p = 0.19). Patients taking painkillers had higher mean VAS scores (49 mm) compared with those not on analgesia (27 mm; p \u3c 0.001). Anti-rheumatic treatment did not influence pain scores (p = 0.13). The VAS is a reliable and effective method of pain assessment. Results are independent of which health professional administers the scale. Patients with rheumatic disease report their pain similarly regardless of diagnosis. However, pain control is sub-optimal in patients taking analgesia. Specific assessment of pain is, thus, important in patients attending rheumatology clinics