Seasonal Depiction of Malariometric Indices in Children under Five Years in a Sudanese Semi-urban Area of Burkina Faso

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 of a 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-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 < 11.0 g/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.