ABSTRACT
Aims:Malariometric indices are essential for the assessment of both new therapies and control strategies. As part of the characterization of a new malaria clinical trial site, this study was carried out to assess malariometric indices during the two seasons ofa Sudanese area of Burkina Faso, in children aged under five years.Study Design:Two community-based cross-sectional surveys were conducted as follow: the first during the rainy season of 2009 and the second during the following dry season. Socio-Original ResearchArticle demographic and clinical data were recorded. A finger prick blood sample was collected to perform malaria blood films and to measure the hemoglobin level.Results:Malaria parasitemia prevalence was 55.2% (N = 677) in the rainy season with a geometric mean of parasite density (GMPD) of 3439 trophozoites/μl against 23.3% (N = 720) in the dry season with a GMPD of 1368 trophozoites/μl. Gametocytemia prevalence was 21.7% and 6.5% respectively in rainy and dry season while splenomegaly prevalence was 11.2% (N = 689) in rainy season against 4.2% (N = 752) in dry season. The prevalence of anemia (hemoglobin < 11.0g/dl) was 90.0% in rainy season and 70.6% in dry season. All indices in rainy season were statistically higher than those in dry season (p-value < 0.0001). The odds of parasite carriage were 3 to 5 times higher in rainy season compared to dry season (95% CI for OR = [3.1, 5.0]).Conclusion:The site is located in a seasonal hyper-endemic malaria area and seems appropriate for the conduct of malaria drugs or vaccines studies. Though the gap between seasons is considerable, the residual level of parasite carriage during low transmission period is not negligible and may command the development of strategies targeting this specific period, to break the chain of transmission of the disease.
ABSTRACT
Background & objectives: Malaria prevention relies heavily on insecticide-treated bednets. Even though the benefits of bednets have been proven that in most of the studies carried out in Africa, their efficacy remains dependent on local conditions. In this study, under field conditions, we evaluated the efficacy of two LLINs (PermaNet® vs Interceptor®) and two bednet treatment kits (K-O TAB® vs Fendona 6SC®) against Anopheles gambiae s.l. Methods: Bednets were evaluated using experimental huts in the village of Pissy located in the Saponé health district of Burkina Faso. Treatments and sleepers were randomly rotated between huts. Results are expressed in terms of induced exophily, mortality after 24 h and blood-feeding inhibition. Results: A total of 1392 An. gambiae s.l. mosquitoes were collected during 120 nights in the experimental huts. The overall mortality rates were 85.4% (CL: 79.7–91.4) and 77.5% (CL: 56.9–97.3) for PermaNet® and Interceptor®, respectively. For the conventionally treated bednets, the mortality was 78.2% (CL: 63.13–96.7) with the Fendona 6SC®-treated nets and 75.5% (CL: 61.2–93) with the K-O TAB®-treated nets. The proportion of blood-fed mosquitoes was significantly higher in the untreated bednet arm than in the treated one, as well as for long-lasting nets than for conventionally treated nets. The entry rate did not vary significantly according to the bednet type, but the treated bednets increased the level of exophily by at least 43%. Conclusion: In the field, the Fendona 6SC® kit and the Interceptor bednets showed comparable efficacy to the already used K-O TAB® kit and PermaNet® bednets. These results could help National Malaria Program managers to formulate appropriate policy for effective vector control.