The use of impregnated curtains does not affect antibody responses against Plasmodium falciparum and complexity of infecting parasite populations in children from Burkina Faso

Abstract In Burkina Faso, where malaria is hyper-endemic and transmission intensity is very high, the majority of malaria-related morbidity and mortality occurs in children less than 5 years of age. A control measure such as the use of insecticide-treated curtains (ITC) significantly reduces transmission of malaria infection. Concerns remain whether reduced transmission intensity may lead to a delay in the development of immunity in younger children and even to a partial loss of already acquired immunity. In this study, the levels of P. falciparum-specific IgG subclasses, the number of infecting parasite clones determined by PCR-based genotyping of the msp2 gene and the parasite density were analysed in 154 asymptomatic children (3–6 years) living in 16 villages (8 with and 8 without ITC) in the vicinity of Ouagadougou, the capital of Burkina Faso. In addition, the parasite inhibitory effects of Ig fractions, prepared from selected children, in co-operation with normal human monocytes were studied. Blood samples from asymptomatic ITC-users showed a significant decrease in P. falciparum prevalence as well as in parasite density. However, no significant difference was observed in P. falciparum-specific antibodies or in parasite multiplicity of infection between the two groups. Furthermore, Ig fractions from children of both groups showed similar levels of inhibitory activity against autologous parasite growth both on their own and in co-operation with monocytes. © 2004 Elsevier B.V. All rights reserved. Keywords: Wild isolate of P. falciparum; Insecticide-treated curtains; Immunit

Trends and risk factors for childhood diarrhea in sub-Saharan countries (1990 2013): assessing the neighborhood inequalities

BACKGROUND: Diarrheal diseases are a major cause of child mortality and one of the main causes of medical consultation for children in sub-Saharan countries. This paper attempts to determine the risk factors and neighborhood inequalities of diarrheal morbidity among under-5 children in selected countries in sub- Saharan Africa over the period 1990 2013. DESIGN: Data used come from the Demographic and Health Survey (DHS) waves conducted in Burkina Faso (1992 93, 1998 99, 2003, and 2010), Mali (1995, 2001, 2016, and 2012), Nigeria (1990, 1999, 2003, 2008, and 2013), and Niger (1992, 1998, 2006, and 2012). Bivariate analysis was performed to assess the association between the dependent variable and each of the independent variables. Multilevel logistic regression modelling was used to determine the fixed and random effects of the risk factors associated with diarrheal morbidity. RESULTS: The findings showed that the proportion of diarrheal morbidity among under-5 children varied considerably across the cohorts of birth from 10 to 35%. There were large variations in the proportion of diarrheal morbidity across countries. The proportions of diarrheal morbidity were higher in Niger compared with Burkina Faso, Mali, and Nigeria. The risk factors of diarrheal morbidity varied from one country to another, but the main factors included the child's age, size of the child at birth, the quality of the main floor material, mother's education and her occupation, type of toilet, and place of residence. The analysis shows an increasing trend of diarrheal inequalities according to DHS rounds. In Burkina Faso, the value of the intraclass correlation coefficient (ICC) was 0.04 for 1993 DHS and 0.09 in 2010 DHS; in Mali, the ICC increased from 0.04 in 1995 to 0.16 in 2012; in Nigeria, the ICC increased from 0.13 in 1990 to 0.19 in 2013; and in Niger, the ICC increased from 0.07 in 1992 to 0.11 in 2012.IS

Landrace sorghum lines- potential sources for male sterility maintainers in hybrid parent development

The potential of hybrid sorghum to provide yield advantages under drought stressed conditions in semiarid areas was shown several authors ( Haussmann, et al., 1998, 2000, Rattunde et al., 2013). Higher yield advantages were shown with Nigerian germplasm in preliminary on-station testing (Andrews, 1975), though the parental materials have since been lost. The objective of this work is to identify suitable seed parents towards developing hybrid sorghum for the Nigerian environment, constrained most particularly by non-appropriate indigenous sources of stable malesterility maintenance on the female parents, within the diversesorghum landraces

Morphological Diversity Assessment of Nigeria Sorghum Landraces for Utilization in Hybrid Parent Development

Challenge in hybrid sorghum development for the Nigerian environment remains the identification of suitable seed parents, constrained most particularly by non-appropriate indigenous sources of stable male-sterility maintenance on the female parents. To achieve this goal, defined “functional” heterotic parental-pools is required to create new and diverse hybrid parents for sustainable hybrid development. To explore availability of male–sterility inducing cytoplasm, an exploratory landrace Sorghum collection across some states of Nigeria 2014 and 2015 were carried out and evaluated for target hybrid parent traits. 388 testcrosses generated from 40 randomly selected landraces collections using 2 male sterile lines (ICS38A and ICS24005A), were evaluated for sterility maintainer to identify lines that are suitable for conversion to male sterile lines and restorers. Preliminary characterization during 2014 cropping season evaluation showed that most of the sorghum landraces grown in the Sudan Savannah are white or yellow grain with compact elliptic panicle forms (caudatum type) accounting for 46% as compared to those in Guinea Savannah cultivating white or red grain with loose dropping panicle forms (guinea type). Result from the genomic analysis revealed wide genetic diversity with 5 major distinct clusters at 0.2 Euclidian distances. The genetic materials used as parents in the testcrosses showed high potential of genetic male sterility maintainers and were diverse, where 3 of the landrace parents were mapped to cluster 1, 13 to cluster 2, 1 to cluster 3 and 3 to cluster 5. Given that the collection areas are diverse with heterogeneous agro-ecologies, the landraces observed could be used as important sources of novel alleles for developing hybrid parents

Insecticide-treated curtains reduce the prevalence and intensity of malaria infection in Burkina Faso

A large, randomized controlled trial to investigate the impact of insecticide-treated curtains (ITC) on child mortality was conducted in an area of seasonal, holoendemic malaria in Burkina Faso. 158 communities totalling some 90,000 people were censused and grouped into 16 geographical clusters, 8 of which were randomly selected to receive ITC in June-July 1994, just prior to the rainy season. In September-October 1995, at the peak period of malaria transmission, a cross-sectional survey was conducted in 84 of the villages. A random sample of 905 children aged 6-59 months was identified and visited. 763 children (84%) were present at the time of the visit and recruited into the study. Mothers were asked about fever in the past 24 h, the child's temperature was taken, and a sample of blood collected to identify and quantify malaria infections and to measure haemoglobin (Hb) levels. Children protected by ITC were less likely to be infected with Plasmodium falciparum (risk ratio = 0.92; 95% CI 0.86, 0.98) or P. malariae (risk ratio = 0.42, 95% CI 0.19, 0.95). The mean intensity of P. falciparum infections was lower among children protected by ITC (899 vs. 1583 trophozoites/microliter; P < 0.001), while the mean Hb level was 0.4 g/dl higher (P < 0.001). While we found no evidence that ITC had an impact on the prevalence of malaria-associated fever episodes, the confidence intervals around our estimates of the impact of ITC on malaria morbidity were wide. We conclude that widespread implementation of ITC in this area of high malaria transmission led to a modest reduction in the prevalence of malaria infection and to a more substantial reduction in the intensity of these infections which caused increased Hb levels. We were unable to demonstrate any impact of ITC on malaria morbidity, but the wide confidence intervals around our point estimates do not preclude the possibility of a substantial impact

Child mortality in a West African population protected with insecticide-treated curtains for a period of up to 6 years

Objectives To determine the impact of insecticide-treated curtains (ITC) on all-cause child mortality (6–59 months) over a period of six years. To determine whether initial reductions in child mortality following the implementation of ITC are sustained over the longer term or whether “delayed” mortality occurs. Methods A rural population of ca 100 000 living in an area with high, seasonal Plasmodium falciparum transmission was studied in Burkina Faso. Annual censuses were conducted from 1993 to 2000 to measure child mortality. ITC to cover doors, windows, and eaves were provided to half the population in 1994 with the remainder receiving ITC in 1996. Curtains were re-treated or, if necessary, replaced annually. Findings Over six years of implementation of ITC, no evidence of the shift in child mortality from younger to older children was observed. Estimates of the reduction in child mortality associated with ITC ranged from 19% to 24%. Conclusions In our population there was no evidence to suggest that initial reduction in child mortality associated with the introduction of insecticide-treated materials was subsequently compromised by a shift in child mortality to older-aged children. Estimates of the impact of ITC on child mortality in this population range from 19% to 24%. Keywords Malaria/epidemiology/mortality; Bedding and linens/utilization/statistics; Child, Preschool; Infant mortality; Plasmodium falciparum/immunology; Malaria, Falciparum/prevention and control/transmission; Anopheles; Mosquito control; Permethrin; Remission induction; Age factors; Regression analysis; Incidence; Survival rate; Randomized controlled trials; Burkina Faso/epidemiology (source: MeSH, NLM). Mots clés Paludisme/épidémiologie/mortalité; Literie et linge/utilisation/statistique; Enfant âge pré-scolaire; Mortalité nourrisson; Plasmodium falciparum/immunologie; Paludisme plasmodium falciparum/prévention et contrôle/transmission; Anophèles; Lutte contre moustique; Perméthrine; Traitement induction rémission; Facteur âge; Analyse régression; Incidence; Taux survie; Essai clinique randomisé; Burkina Faso/épidémiologie (source: MeSH, INSERM). Palabras clave Paludismo/epidemiología/mortalidad; Ropa de cama y ropa blanca/utilización/estadística; Infante; Mortalidad infantil; Plasmodium falciparum/inmunología; Paludismo falciparum/prevención y control/ transmisión; Anopheles; Control de mosquitos; Permetrina; Inducción de remisión; Factores de edad; Análisis de regresión; Incidencia; Tasa de supervivencia; Ensayos controlados aleatorios; Burkina Faso/epidemiología (fuente: DeCS, BIREME). Bulletin of the World Health Organization 2004;82:85-91

Etude de l’influence des modes de transformation sur les teneurs en lycopène de quatre variétés de tomates de la région du nord du Burkina Faso

Les traitements thermiques visent à stabiliser les aliments pour de longues périodes de stockage. Ils induisent des variations dans la composition de l’aliment. Le présent travail a pour but d’évaluer l’influence des modes de transformation (séchage, cuisson) sur les teneurs en lycopène de quatre variétés de tomates (Mongal F1, Tropimech, Royale et Rio Grande) de la région nord du Burkina Faso. Les résultats en milligrammes de lycopène par gramme de tomates sont ainsi exprimés : Purée : Tropimech (0,065), Mongal F1 (0,028), Royale (0,051) et Rio Grande (0,045. Après les traitements on a noté les évolutions suivantes : Séchage à l’ombre : Tropimech (- 0.009), Mongal F1 (+0.009) Royale (-0.010) et Rio Grande (-0.009). Séchage solaire : Tropimech (-0.021), Mongal F1 (-0.007) Royale (-0.011) et Rio Grande (-0.014). Cuisson : Tropimech (-0.038), Mongal F1 (-0.014), Royale (-0.025) et Rio Grande (-0.024). Séchage solaire puis cuisson : Tropimech (-0.044),  Mongal F1 (-0.017), Royale (-0.038) et Rio Grande (-0.0035). Séchage ombre puis cuisson: Tropimech (-0.045),  Mongal F1 (-0.018), Royale (-0.035) et Rio Grande (-0.033). D’une  manière générale, les teneurs en lycopène ont subi une baisse au cours de la transformation.Mots clés : Tomates, lycopène, mode de transformation

Genetic Potentials of Landrace Sorghum Genotypes for Enhanced Micronutrient(Iron and Zinc) Nutrition in West Africa

Micronutrient malnutrition, is one of greatest global challenges of our times with devastating consequences on health. Commonly used interventions associated with high cost and short-term benefits includes: nutrient supplementation, dietary diversification, commercial fortification, nutritional education and agricultural interventions

Plasmodium falciparum merozoite surface protein 2: epitope mapping and fine specificity of human antibody response against non-polymorphic domains.

BACKGROUND: Two long synthetic peptides representing the dimorphic and constant C-terminal domains of the two allelic families of Plasmodium falciparum merozoite surface proteins 2 are considered promising malaria vaccine candidates. The aim of the current study is to characterize the immune response (epitope mapping) in naturally exposed individuals and relate immune responses to the risk of clinical malaria. METHODS: To optimize their construction, the fine specificity of human serum antibodies from donors of different age, sex and living in four distinct endemic regions was determined in ELISA by using overlapping 20 mer peptides covering the two domains. Immune purified antibodies were used in Western blot and immunofluorescence assay to recognize native parasite derivate proteins. RESULTS: Immunodominant epitopes were characterized, and their distribution was similar irrespective of geographic origin, age group and gender. Acquisition of a 3D7 family and constant region-specific immune response and antibody avidity maturation occur early in life while a longer period is needed for the corresponding FC27 family response. In addition, the antibody response to individual epitopes within the 3D7 family-specific region contributes to protection from malaria infection with different statistical weight. It is also illustrated that affinity-purified antibodies against the dimorphic or constant regions recognized homologous and heterologous parasites in immunofluorescence and homologous and heterologous MSP2 and other polypeptides in Western blot. CONCLUSION: Data from this current study may contribute to a development of MSP2 vaccine candidates based on conserved and dimorphic regions thus bypassing the complexity of vaccine development related to the polymorphism of full-length MSP2

Antibodies to malaria vaccine candidates are associated with chloroquine or sulphadoxine/pyrimethamine treatment efficacy in children in an endemic area of Burkina Faso

<p>Abstract</p> <p>Background</p> <p>Patient immune status is thought to affect the efficacy of anti-malarial chemotherapy. This is a subject of some importance, since evidence of immunity-related interactions may influence our use of chemotherapy in populations with drug resistance, as well as assessment of the value of suboptimal vaccines. The study aim was to investigate relationship between antibodies and anti-malarial drug treatment outcomes.</p> <p>Methods</p> <p>Some 248 children aged 0.5 and 15 years were recruited prior to the high malaria transmission season. Venous blood (5 ml) was obtained from each child to measure antibody levels to selected malaria antigens, using ELISA. Blood smears were also performed to assess drug efficacy and malaria infection prevalence. Children were actively followed up to record clinical malaria cases.</p> <p>Results</p> <p>IgG levels to MSP3 were always higher in the successfully treated group than in the group with treatment failure. The same observation was made for GLURP but the reverse observation was noticed for MSP1-19. Cytophilic and non-cytophilic antibodies were significantly associated with protection against all three antigens, except for IgG4 to MSP1-19 and GLURP.</p> <p>Conclusion</p> <p>Acquired anti-malarial antibodies may play an important role in the efficacy of anti-malarial drugs in younger children more susceptible to the disease.</p