[Effect of a large scale community-based distribution of artemether-lumefantrine on its therapeutic efficacy among children living in a rural area of Burkina Faso]. / Effet d'une distribution communautaire à large échelle de l'artéméther-luméfantrine sur son efficacité thérapeutique chez les enfants vivant en milieu rural au Burkina Faso.

This study aimed to assess the effect of an integrated community case management of malaria and pneumonia programme (iCCMmp) on the efficacy of artemether-lumefantrine (AL). Thus, we carried out two open label and unique centre clinical trials, before and after the iCCMmp, on the therapeutic efficacy of AL. A total of 210 children aged 6-59 months, were included in the study, 105 before and 105 after the iCCMmp. The adequate clinical and parasitological response was 90.5% and 86.7% respectively before and after the iCCMmp (p value = 0.516). Our findings reported no effect of iCCMmp on the therapeutic efficacy of the AL.

[Efficacy of artemether-lumefantrine in the treatment of uncomplicated malaria in children living in a rural area of Burkina Faso in 2009]. / Efficacité de l'artéméther-luméfantrine dans le traitement du paludisme simple de l'enfant en milieu rural au Burkina Faso en 2009.

In order to implement community case management of malaria strategy in a rural area of intense transmission, of children using artemether-lumefantrine combination, we assessed the therapeutic efficacy of the medicine. We conducted an open label and uncontrolled clinical trial in an unique centre from September 2009 to December 2009 in children 6-59 months old who consulted at health facilities for uncomplicated malaria. The primary endpoint was clinical and parasitological cure rate at day 28 corrected by PCR. In total 106 children were enrolled. Parasite clearance at day 2 was 99.04% and the adequate clinical and parasitological response corrected by PCR at day 28 was 90.5%. Our results confirm that artemether-lumefantrine combination is still effective.

Humoral and cell-mediated immunity to MSP3 peptides in adults immunized with MSP3 in malaria endemic area, Burkina Faso.

We performed a single-blind, randomized phase 1 trial of the long synthetic peptide (LSP) of merozoite surface protein-3 (MSP3) in adults living in Burkina Faso. Thirty eligible volunteers were randomized to receive either the MSP3-LSP candidate vaccine or tetanus toxoid vaccine as a control. A dose of each vaccine was administered on days 0, 28 and 112 and the vaccine was formulated with aluminium hydroxide. Humoral immune responses were assessed by ELISA at days 0, 28, 56, 112, 140, 252 and 365 and cell-mediated immune responses by lymphoproliferation assay and by ELISA on days 0, 56 and 140. IgG responses to four peptides of MSP3 were similar in both vaccine groups. Higher IgG concentrations were recorded after the beginning of malaria high transmission season in both vaccine groups. The lymphocyte proliferation and the production of IFN-gamma in response to stimulation with the four overlapping peptides increased following vaccination in the MSP3-LSP vaccine group, but did not change appreciably in the control group. In contrast to natural infection, MSP3-LSP did not boost humoral responses to the four overlapping peptides of MSP3 to any detectable degree in our semi-immune adult. MSP3-LSP may be more immunogenic in young children with little or no acquired immunity.

[Pharmaceutical black market in Burkina Faso: an illicit but socially adapted market]. / Le marché parallèle des médicaments au Burkina Faso: un marché dit illicite mais socialement construit.

In recent years the sale of pharmaceutical products by unlicensed vendors outside the official public health system has grown in Africa in general and in Burkina Faso in particular. The purpose of the present study was to identify the persons involved and their motivations, sources of supply, chains of distribution, and strengths and weaknesses of the parallel market. Data were collected using a two-part questionnaire. The first part focused on a certain category of buyer, i.e., mothers with children under the age of 5 years and the second part focused on medicine vendors working outside the official system. Accidental sample allowed contact with 41 vendors and cluster sampling obtained 340 mothers whose children presented fever within the last 30 days. Illicit sale of medicine appears to involve mainly young males with little or no formal education. The sex ratio was 0.25 including 34.1% with schooling and 65.9% with no schooling. The main motives of the vendors were money (18/41) and unemployment (12/41). The remaining 11 vendors stated that they wanted to help people who did not have access to a nearby health center. The business appears to be lucrative since the average daily income was estimated at 2.815 F CFA (ranges: 255 F CFA to 10.000 F CFA). Customers stated several reasons for buying on the illicit market but the most frequent reason was affordability. According to 98% of mothers drugs were cheaper on the illicit market than on the official market. Most mothers declared that their resources were insufficient to purchase higher-priced licit pharmaceutical products. Other factors accounted for buying drugs on the parallel market. Although it is considered as illicit, the market has the advantage of being socially adapted and responsive to consumer habits, expectations and needs.

[Change of antimalarial first-line treatment in Burkina Faso in 2005]. / Les raisons d'un changement de médicaments de première intention pour le traitement du paludisme simple au Burkina Faso en 2005.

Burkina Faso has recently changed the antimalarial drug policy to artesunate/amodiaquine or artemether/lumefantrine as the first-line antimalarial drug and sulfadoxine/pyrimethamine for the intermittent preventive treatment in pregnant woman. Before the implementation of this new strategy we conducted an in vivo efficacy study with chloroquine or sulfadoxine/pyrimethamine for treatment of uncomplicated Plasmodium falciparum malaria in urban area of Burkina from September to December 2003. Chloroquine (25 mg/kg over 3 days) or sulfadoxine/pyrimethamine (25 mg/kg + 0.025 mg/kg single dose) was administered respectively to 137 and 125 children aged from 6 to 59 months old in a randomized, opened study. Follow up extended over 28 days using modified WHO protocol. After adjusting the results by PCR, treatment failures rates were 63.4% (83/131) and 13.8% (17/123) respectively for chloroquine and sulfadoxine/pyrimethamine. These results with other observations have justified the change of malaria therapy policy in Burkina Faso in 2005.

Do antibody responses to malaria vaccine candidates influenced by the level of malaria transmission protect from malaria?

OBJECTIVES: To examine whether the humoural response to malaria vaccine candidate antigens, Plasmodium falciparum [circumsporozoite repetitive sequence (NANP)(5) GLURP fragments (R0 and R2) and MSP3] varies with the level of malaria transmission and to determine whether the antibodies (IgG) present at the beginning of the malaria transmission season protect against clinical malaria. METHODS: Cross-sectional surveys were conducted to measure antibody response before, at the peak and at the end of the transmission season in children aged 6 months to 10 years in two villages with different levels of malaria transmission. A cohort study was performed to estimate the incidence of clinical malaria. RESULTS: Antibodies to these antigens showed different seasonal patterns. IgG concentrations to any of the four antigens were higher in the village with high entomological inoculation rate. Multivariate analysis of combined data from the two villages indicated that children who were classified as responders to the selected antigens were at lower risk of clinical malaria than children classified as non-responders [(NANP)(5) (incidence rate ratio (IRR) = 0.65, 95% CI: 0.46-0.92; P = 0.016), R0 (IRR = 0.69, 95% CI: 0.48-0.97; P = 0.032), R2 (IRR = 0.73, 95% CI: 0.50-1.06; P = 0.09), MSP3 (IRR = 0.52, 95% CI: 0.32-0.85; P = 0.009)]. Fitting a model with all four antibody responses showed that MSP3 looked the best malaria vaccine candidate (IRR = 0.63; 95% CI: 0.38-1.05; P = 0.08). CONCLUSION: Antibody levels to the four antigens are affected by the intensity of malaria transmission and associated with protection against clinical malaria. It is worthwhile investing in the development of these antigens as potential malaria vaccine candidates.

[Comparative impact of three malaria preventive regimens during pregnancy on maternal anemia due to malaria in Burkina Faso]. / Impact comparatif de trois schémas de prévention du paludisme pendant la grossesse sur l'anémie maternelle, associée à l'infection palustre au Burkina Faso.

OBJECTIVES: The main objective of this study was to compare the efficacy of three regimens of malaria prevention during pregnancy for the reduction of anemia between the first and third antenatal consultations. The first treatment arm was the classical weekly chemoprophylaxis with chloroquine; the other two were the intermittent preventive treatment using either three doses of chloroquine or sulfadoxine-pyrimethamine. DESIGN: We conducted an open, randomized, three-arm study in a rural district of Burkina Faso. A cohort was constituted by 648 pregnant women of any parity. RESULTS: The hemoglobin gain was more significant with the intermittent preventive treatment using sulfadoxine-pyrimethamine compared to the other treatment arms. The hemoglobin increased from 10.3g/dl (at the first antenatal consultation) to 11.4 g/dl (at the third antenatal consultation). In the three arms of treatment, the chemoprophylaxis reduced the prevalence of moderate anemia and severe anemia. The reduction of moderate anemia was more substantial in the sulfadoxine-pyrimethamine arm (65.6 to 36.7%) at second antenatal consultation (p=0.069) and third antenatal consultation (p=0.014). Conversely, in the two chloroquine arms, there was no significant reduction either at second antenatal consultation (p=0.72) or third antenatal consultation (p=0.55). The prevalence of peripheral parasitemia decreased in all treatment groups. However, it was significantly higher in the sulfadoxine-pyrimethamine group (44.3%). CONCLUSIONS: Intermittent preventive treatment with three doses of sulfadoxine-pyrimethamine is a more effective strategy to prevent maternal anemia during pregnancy in Burkina Faso.

[Genetic diversity of P. falciparum and pathogenesis of the severe malarial anaemia in children under 5 years old in the province of Boulgou, Burkina Faso]. / Diversité génétique de Plasmodium falciparum et pathogénie de l'anémie palustre sévere chez des enfants de moins de 5 ans de la province du Boulgou, Burkina Faso.

The clinical presentation of malaria mainly the severe form may be related to Plasmodium falciparum msp-2 (merozoite surface protein 2) specific family To verify this hypothesis, during the high malaria transmission season in 2001; we analyzed the allelic polymorphism of the msp-2 gene of P. falciparum in children under 5 years old with different presentation of malaria in the regional Hospital and at community level in the Boulgou Province (Burkina Faso). A total of 405 children (107 severe malarial anaemia cases, 102 severe malaria cases without severe anaemia and 196 non severe malaria cases) were enrolled in the study. The frequencies of the FC27 were 89.2% in severe malarial anaemia children group, then 89.7% and 86.9% respectively in severe malaria non anaemic children cases and non severe malaria cases (P = 0.4). The frequencies of the 3D7 were 72.5%; 84.1% and 77% respectively severe malaria non anaemic children, severe malarial anaemia cases and non severe malaria cases (P = 0.7). The complexity of the FC27 genotypes was significantly higher in children with severe malaria (with and without severe anaemia) compared to the non severe malarial children (P << 0.001). No significant difference was pointed up in the complexity of the 3D7 genotypes.

Natural antibody response to Plasmodium falciparum Exp-1, MSP-3 and GLURP long synthetic peptides and association with protection.

A longitudinal study was undertaken in Burkina Faso among 293 children aged 6 months to 9 years in order to determine the correlation between an antibody response to several individual malarial antigens and malarial infection. It was found that the presence of a positive antibody response at the beginning of the rainy season to three long synthetic peptides corresponding to Plasmodium falciparum Exp-1 101-162, MSP-3 154-249 and GLURP 801-920 but not to CSP 274-375 correlated with a statistically significant decrease in malarial infection during the ongoing transmission season. The simultaneous presence of an antibody response to more than one antigen is indicative of a lower frequency of malarial infection. This gives scientific credibility to the notion that a successful malaria vaccine should contain multiple antigens.