Aspects épidémiologiques et caractérisation moléculaire des souches du virus de l’hépatite E (VHE) au Burkina Faso

The hepatitis E virus (HEV) is causative agent several acute or fulminant hepatitis which mainly occur in developing countries where HEV genotype 1 or 2 appears to have a endemic profile punctuated with epidemic outbreaks (Africa, Asia) (Lui et al., 2013). Genotype 3 and 4 distributed widely in animal reservoirs, were the cause many zoonotic infection in northern and southern countries. In most cases, it is a self-limited infection with rapid viral clearance, but it can evolve into more severe forms with a mortality level ranging from 1 to 4% in the general population to nearly 20% in pregnancy during outbreaks (WHO, 2014). In Burkina Faso, very little epidemiological data are available on HEV. The objective of this work is to improve our understanding of this agent hepatitis. The first part of our study was devoted to the evaluation HEV seroprevalence among blood donors and women attending antenatal care in Ouagadougou. In total more than 1,700 volunteers serum samples were collected in blood banks and medical centers in Burkina Faso. Between 2010 and 2012 on 178 blood donors and 189 pregnant women tested, 19.1% [CI95, 13.3-24.9%] and 11.6% [CI95, 7.1-16.2%], were respectively positive for anti-HEV IgG. These high rates in the general population may be associated a low income and the poor hygienic status (Traoré et al., 2012). In 2014, 3.19% [CI95, 1.70-4.68%] on 525 blood donors tested, were positive for anti-HEV IgM. These results indicate a residual risk for transfusion, probably associated with silent infections and confirm the importance to identify the sources of the virus. The second part of this work was 1) to assess HEV infection among humans in Burkina Faso by exploring the HEV seroprevalence in a high risk population, i.e., butchers; 2) to explore a possible pig-to-human zoonotic transmission cycle by assessing the HEV seroprevalence in slaughter swine; and 3) to identify the genotype of HEV circulating in pigs. The global HEV prevalence among Ouagadougou butchers was estimated to 76%, CI95 [67, 63–84.37%] with a significant risk factor, 3 times higher compared with the general population (OR = 3.46 [95%CI 2.85 - 4.21] p 98% was found between swHEV-BF from Yaounde and Madagascar. This data showed for the first time the role of swine in introduction of new HEV in African population. In conclusion, these results latter sign a persistent introduction of HEV infection in the population and hence deserved to be taken in account in transfusion associated risk. Further assessments of the transfusion risk associated require an evaluation of the cost/benefit ratio for the addition of routine HEV RNA screening to the panel of tests on donated blood, to guarantee transfusion safety for the recipient.Le virus de l’hépatite E (VHE) est l’agent causal d’une partie des hépatites aigues ou fulminantes qui surviennent essentiellement dans les pays en voie de développement (Afrique, Asie) ou le VHE de génotype 1 semble présenter un profil endémique ponctué de bouffées épidémiques souvent liées à des déplacements de populations (catastrophe climatique ou conflits) (Lui et al., 2013). Récemment il a été montré que ce virus était largement distribué dans des réservoirs animaux (génotype 3 et 4) et la cause d’un grand nombre d’infections zoonotiques aussi bien dans les pays du nord que du sud. Dans la plupart des cas, il s'agit d'une infection spontanément résolutive avec une clairance virale rapide, mais il peut évoluer vers des formes plus sévères avec un niveau de mortalité variant de 1 à 4% dans la population générale et à près de 20% chez la femme enceinte lors des flambées épidémiques (OMS, 2014). Au Burkina Faso, très peu de données existent sur la prévalence chez l’homme, l'épidémiologie moléculaire du VHE ou la présence de ce virus dans le réservoir animal principal que constituent les porcs. De plus, l’ignorance de la population quant aux causes de cette infection d’origine alimentaire, est un facteur de risque qu’on ne peut pas ignorer. L’objectif de ce travail est donc d’améliorer notre connaissance sur cet agent des hépatites. La première partie de notre étude s’est consacrée à l’évaluation de la séroprévalence du VHE chez les donneurs de sang et les femmes venant en consultation prénatale à Ouagadougou. Au total plus de 1700 échantillons de sérums de volontaires ont été collectés dans les banques de sang et centres médicaux: entre 2010 et 2012, sur les 178 donneurs de sang et 189 femmes enceintes testés, 19,1% [IC95, 13,3-24,9%] et 11,6% [IC95, 7,1-16,2%] étaient respectivement positifs aux IgG anti-VHE. Ces taux élevés sont peut-être associé au faible statut socioéconomique et à l’absence de réseaux d’assainissement des eaux (Traoré et al., 2012). En 2014, 3,19% [IC95, 1,70-4,68%] des 533 donneurs de sang testé sont positifs pour des IgM anti-VHE. Ces résultats montrent un risque résiduel transfusionnel non négligeable associé à une transmission à bas bruit et confirme l’intérêt d’identifier la ou les sources de ce virus. La seconde partie de ce travail a été de vérifier le rôle d’une source zoonotique des infections à VHE, via l’évaluation du VHE (par sérologie et typage moléculaire après PCR) dans le réservoir potentiel que sont les porcs et la population à risques exposé à ce réservoir (bouchers et éleveurs). Pour cela nous avons réalisé un recensement des sites de ventes de porcs et évalué la consommation d’animaux. Un taux de séroprévalence de 76% [IC95, 67,6-84,4%] a été mesuré dans une cohorte de 100 bouchers de Ouagadougou avec un facteur de risque de séropositivité 3 fois plus élevé par rapport à la population générale (OR = 3,46 [95%CI 2,85 – 4,21] p <0.001). Les IgG anti-VHE chez les porcs abattus ont été estimés à 80% IC95 [72-87%]. Cette forte prévalence confirme une circulation silencieuse du VHE dans l’élevage porcin au Burkina Faso comme en témoigne l'échantillon positif de foie pour l’ARN VHE qui soutient fermement le risque de zoonose. L’analyse des séquences des produits de PCR des foies de porcs positifs pour VHE a révélé la présence de VHE génotype 3 et 99,8 % d'homologie avec les souches Yaounde et Madagascar. En conclusion, notre étude, la première caractérisation moléculaire des souches du VHE au Burkina, montre la présence de souches VHE génotype 3 dans des régions ou seul le génotype 1 avait été identifié jusqu’alors (Tchad, Maroc). L’évaluation du risque transfusionnel associé nécessite des études complémentaires afin d’évaluer le bénéfice/coût de l'ajout de dépistage du VHE dans les examens de routines des banques de sang, afin de garantir la sécurité du receveur de sang

Effets de la Politique Fiscale Sur la Croissance Économique du Mali

L’objectif de cette étude était d’examiner les effets de la politique fiscale sur la croissance économique au Mali durant la période 1990-2021, en utilisant le modèle autorégressif à décalage distribué (ARDL), principalement en raison de l'ordre d'intégration des variables utilisées. Les résultats empiriques ont révélé qu'il existe une relation positive entre les instruments de politique fiscale (impôt sur le revenu et dépenses publiques) et la croissance économique. Sur la base des résultats, l'étude recommande au gouvernement de faire la distinction entre les dépenses productives et improductives et d'augmenter les dépenses. L'implication de ces résultats est que l'économie du Mali est susceptible d'être plus performante si davantage de ressources sont détournées de la consommation du gouvernement vers les dépenses d'investissement. &nbsp; The objective of this study was to examine the effects of fiscal policy on economic growth in Mali during the period 1990-2021, using the autoregressive distributed lag model (ARDL), mainly because of the order of integration of the variables used. The empirical results revealed that there is a positive relationship between fiscal policy instruments (income tax and government spending) and economic growth. Based on the results, the study recommends that the government distinguish between productive and unproductive expenditures and increase spending. The implication of these results is that Mali's economy is likely to perform better if more resources are diverted from government consumption to investment spending

Effets de la Politique Fiscale Sur la Croissance Économique du Mali

L’objectif de cette étude était d’examiner les effets de la politique fiscale sur la croissance économique au Mali durant la période 1990-2021, en utilisant le modèle autorégressif à décalage distribué (ARDL), principalement en raison de l'ordre d'intégration des variables utilisées. Les résultats empiriques ont révélé qu'il existe une relation positive entre les instruments de politique fiscale (impôt sur le revenu et dépenses publiques) et la croissance économique. Sur la base des résultats, l'étude recommande au gouvernement de faire la distinction entre les dépenses productives et improductives et d'augmenter les dépenses. L'implication de ces résultats est que l'économie du Mali est susceptible d'être plus performante si davantage de ressources sont détournées de la consommation du gouvernement vers les dépenses d'investissement. &nbsp; The objective of this study was to examine the effects of fiscal policy on economic growth in Mali during the period 1990-2021, using the autoregressive distributed lag model (ARDL), mainly because of the order of integration of the variables used. The empirical results revealed that there is a positive relationship between fiscal policy instruments (income tax and government spending) and economic growth. Based on the results, the study recommends that the government distinguish between productive and unproductive expenditures and increase spending. The implication of these results is that Mali's economy is likely to perform better if more resources are diverted from government consumption to investment spending

Implementation of Home based management of malaria in children reduces the work load for peripheral health facilities in a rural district of Burkina Faso

<p>Abstract</p> <p>Background</p> <p>Home Management of Malaria (HMM) is one of the key strategies to reduce the burden of malaria for vulnerable population in endemic countries. It is based on the evidence that well-trained communities health workers can provide prompt and adequate care to patients close to their homes. The strategy has been shown to reduce malaria mortality and severe morbidity and has been adopted by the World Health Organization as a cornerstone of malaria control in Africa. However, the potential fall-out of this community-based strategy on the work burden at the peripheral health facilities level has never been investigated.</p> <p>Methods</p> <p>A two-arm interventional study was conducted in a rural health district of Burkina Faso. The HMM strategy has been implemented in seven community clinics catchment's area (intervention arm). For the other seven community clinics in the control arm, no HMM intervention was implemented. In each of the study arms, presumptive treatment was provided for episodes of fevers/malaria (defined operationally as malaria).</p> <p>The study drug was artemether-lumefantrine, which was sold at a subsidized price by community health workers/Key opinion leaders at the community level and by the pharmacists at the health facility level.</p> <p>The outcome measured was the proportion of malaria cases among all health facility attendance (all causes diseases) in both arms throughout the high transmission season.</p> <p>Results</p> <p>A total of 7,621 children were enrolled in the intervention arm and 7,605 in the control arm. During the study period, the proportions of malaria cases among all health facility attendance (all causes diseases) were 21.0%, (445/2,111, 95% CI [19.3%–22.7%]) and 70.7% (2,595/3,671, 95% CI 68.5%–71.5%), respectively in the intervention and control arms (p << 0.0001). The relative risk ratio for a fever/malaria episode to be treated at the HF level was 30% (0.30 < RR < 0.32).</p> <p>The number of malaria episodes treated in the intervention arm was much higher than in the control arm (6,661 vs. 2,595), with malaria accounting for 87.4% of all disease episodes recorded in the intervention area and for 34.1% in the control area (P < 0.0001). Of all the malaria cases treated in the intervention arm, only 6.7% were treated at the health facility level.</p> <p>Conclusion</p> <p>These findings suggest that implementation of HMM, by reducing the workload in health facilities, might contributes to an overall increase of the performance of the peripheral health facilities.</p

Influence of Agro-Ecological Areas on the Antioxidant Capacity of Onion Varieties Grown in Burkina Faso

Colored onion bulb is an important source of antioxidants. Some ecological factors can significantly influence the content and quality of these substances. The aim of the present study is to determine the antioxidant and total polyphenol content of fresh bulbs of five (05) varieties of onion (Galmi Violet, Damani Violet, Prema, Safari and a Local variety-LV) grown in Burkina Faso, and to evaluate also the influence of agro-ecological parameters on the antioxidant content of the most cultivated variety (Galmi violet) of them. Samples of onion bulb for analysis were collected in the six agro-ecological areas of Burkina Faso under the same cultivation conditions. Antioxidant activities were evaluated using the method of Ferric Reducing Antioxidant Power. The evaluation of the total polyphenol contents was carried out using the Folin-Ciocalteu method. The results showed that antioxidant activities for the 5 varieties tested vary between 0.125 ± 0.001 and 0.149 ± 0.004 mg TE / g, and total polyphenol contents from 0.172 ± 0.011 to 0.272 ± 0.003 mg EAG/g. Results on the assessment of the effect of ecology on the antioxidant content of Galmi violet variety revealed significant variations in antioxidant content from 0.144 ± 0.002 to 0.155 ± 0.001 mg TE / g, and total polyphenols from 0.208 ± 0.014 to 0.292 ± 0.012 mg EAG / g depending on the ecological cultivation area

Influences of Storage Conditions, Cultivation and Culinary Practices, On the Antioxidant Capacity of Red Bulbs of Some Onion Varieties Grown in Burkina Faso

Red onion bulb is a vegetable containing micronutrients with antioxidant properties. However, certain factors can have an impact on the content of these compounds. The present research evaluate the effects of parameters such as cultural practices, storage conditions and culinary practices, on the antioxidants content of red onion bulb of some varieties grown in Burkina Faso. The identification of the factors was carried out through field surveys, and their effects on the antioxidants content were assessed and appreciated through especially specific related bibliographic and laboratory test data. The results showed that84.78% of farmers use chemical fertilizers and all of them use chemical pesticides on onion crop. They don’t use premises or equipment suitable for storage. About dishes,7.61% of cooks, peel, cut and wash onion bulb before steam cooking, boiling water cooking or oil frying them at high temperature during 30 minutes to 3 hours. Some cooks use to braise onion bulb scales as ingredients for different dishes such as barbecue. Only 02,72% of cooks grind the onion bulbs with a pestle, before using the crushed as such on barbecue, or slow cooking it in different sauces. Research results show that these culinary practices contribute declining significantly the final intake of antioxidant for the consumer's body

The distribution of hatching time in Anopheles gambiae

BACKGROUND: Knowledge of the ecological differences between the molecular forms of Anopheles gambiae and their sibling species, An. arabiensis might lead to understanding their unique contribution to disease transmission and to better vector control as well as to understanding the evolutionary forces that have separated them. METHODS: The distributions of hatching time of eggs of wild An. gambiae and An. arabiensis females were compared in different water types. Early and late hatchers of the S molecular form were compared with respect to their total protein content, sex ratio, development success, developmental time and adult body size. RESULTS: Overall, the distribution of hatching time was strongly skewed to the right, with 89% of the eggs hatching during the second and third day post oviposition, 10% hatching during the next four days and the remaining 1% hatching over the subsequent week. Slight, but significant differences were found between species and between the molecular forms in all water types. Differences in hatching time distribution were also found among water types (in each species and molecular form), suggesting that the eggs change their hatching time in response to chemical factors in the water. Early hatchers were similar to late hatchers except that they developed faster and produced smaller adults than late hatchers. CONCLUSION: Differences in hatching time and speed of development among eggs of the same batch may be adaptive if catastrophic events such as larval site desiccation are not rare and the site's quality is unpredictable. The egg is not passive and its hatching time depends on water factors. Differences in hatching time between species and molecular forms were slight, probably reflecting that conditions in their larval sites are rather similar