Background. Malaria during pregnancy contributes to maternal anemia and low birth weight. In East Africa, several studies have demonstrated that intermittent preventive treatment (IPT) with sulfadoxine-pyrimethamine (SP) is more efficacious than weekly chloroquine (CQ) chemoprophylaxis in preventing these adverse consequences. To our knowledge, there are no published trials evaluating IPT in West Africa. Methods. We undertook a randomized controlled trial of weekly CQ chemoprophylaxis, 2-dose IPT with CQ, and 2-dose IPT with SP; 1163 women were enrolled. Results. In multivariate analyses, when compared with weekly CQ, IPT/SP was associated with a reduction in third-trimester anemia (adjusted odds ratio [AOR], 0.49; P = .001), placental parasitemia (AOR, 0.69; P = .04), and low birth weight (2 doses may be required to prevent placental reinfection prior to delivery.

Blastocystis is the most common protozoan colonizing the gut of vertebrates. It modulates the human digestive microbiota in the absence of inflammation and gastrointestinal disease. Although it has been associated with human diseases, including inflammatory bowel disease, its pathogenicity remains controversial. This study aimed to assess the influence of Blastocystis on the gut bacterial communities in healthy children. We conducted a cross-sectional study on 147 Blastocystis-colonized and 149 Blastocystis-noncolonized Malian children, with Blastocystis colonization assessed by real-time PCR and gut microbial communities characterized via 16S rRNA gene (Illumina MiSeq) sequencing and bioinformatics analysis. The gut microbiota diversity was higher in Blastocystis-colonized compared to Blastocystis-noncolonized children. The phyla Firmicutes, Elusimicrobia, Lentisphaerae, and Euryarchaeota were higher in Blastocystis-colonized children, whereas Actinobacteria, Proteobacteria, unassigned bacteria, and Deinococcus–Thermus were higher in Blastocystis-noncolonized children. Moreover, Faecalibacterium prausnitzii (family Ruminococcaceae) and Roseburia sp. (family Lachnospiraceae) abundance was higher in Blastocystis-colonized children. We conclude that Blastocystis colonization is significantly associated with a higher diversity of the gut bacterial communities in healthy children, while it is not associated with the presence of potentially pathogenic bacteria in the human gut.

Plasmodium vivax was thought to infect only the erythrocytes of Duffy blood group positive people. In the last decade, P. vivax has appeared throughout Africa, both in areas where Duffy positive and negative people live side by side as in Madagascar and Ethiopia and in areas where people are primarily Duffy negative, such as in western Kenya. We performed quantitative polymerase chain reaction on blood samples dried onto filter paper to determine the prevalence of P. vivax and Plasmodium falciparum in a cohort of 300 children (newborn to 6 years of age) in Bandiagara, a Sahelian area of Mali, west Africa, where the people are Duffy negative. We report 1–3 occurrences of P. vivax in each of 25 Duffy-negative children at six time points over two rainy seasons and the beginning of the third season. The prevalence of P. vivax infection was 2.0–2.5% at every time point (June 2009 to June 2010). All children with P. vivax infections were asymptomatic and afebrile, and parasite densities were extremely low. Anemia, however, was the main burden of infection. Plasmodium vivax could become a burden to sub-Saharan Africa, and the evidence of P. vivax existence needs to be taken into consideration in designing malaria control and elimination strategies in Africa.

The recent decline in malaria incidence in many African countries has been attributed to the provision of prompt and effective anti-malarial treatment using artemisinin-based combination therapy (ACT) and to the widespread distribution of long-lasting, insecticide-treated bed nets (LLINs). At a malaria vaccine-testing site in Bandiagara, Mali, ACT was introduced in 2004, and LLINs have been distributed free of charge since 2007 to infants after they complete the Expanded Programme of Immunization (EPI) schedule and to pregnant women receiving antenatal care. These strategies may have an impact on malaria incidence. To document malaria incidence, a cohort of 400 children aged 0 to 14 years was followed for three to four years up to July 2013. Monthly cross-sectional surveys were done to measure the prevalence of malaria infection and anaemia. Clinical disease was measured both actively and passively through continuous availability of primary medical care. Measured outcomes included asymptomatic Plasmodium infection, anaemia and clinical malaria episodes. The incidence rate of clinical malaria varied significantly from June 2009 to July 2013 without a clear downward trend. A sharp seasonality in malaria illness incidence was observed with higher clinical malaria incidence rates during the rainy season. Parasite and anaemia point prevalence also showed seasonal variation with much higher prevalence rates during rainy seasons compared to dry seasons. Despite the scaling up of malaria prevention and treatment, including the widespread use of bed nets, better diagnosis and wider availability of ACT, malaria incidence did not decrease in Bandiagara during the study period.

Heterogeneous patterns of malaria transmission are thought to be driven by factors including host genetics, distance to mosquito breeding sites, housing construction, and socio-behavioural characteristics. Evaluation of local transmission epidemiology to characterize malaria risk is essential for planning malaria control and elimination programmes. The use of geographical information systems (GIS) techniques has been a major asset to this approach. To assess time and space distribution of malaria disease in Bandiagara, Mali, within a transmission season, data were used from an ongoing malaria incidence study that enrolled 300 participants aged under six years old”.

Treating malaria before immunizing has been standard in malaria vaccine field trials. To assess the impact of this practice on subsequent infection and disease incidence, we conducted a randomized cohort study in Bandiagara, Mali. Subjects received a treatment dose of sulfadoxine-pyrimethamine (SP) or no treatment at the beginning of the transmission season. Cumulative and age-specific incidence of clinical episodes was similar between the 2 groups, but SP treatment delayed the median time to first clinical episode from 38.5 to 68 days, and after this initial period of protection, disease incidence in the SP group quickly surpassed the incidence in the untreated group. Parasite densities during disease episodes were lower in the SP group. SP was chosen as the drug for initial parasite clearance for the following reasons: 1) it has been used in previous vaccine trials; 2) our studies have found it to have >99% efficacy in treating uncomplicated malaria in Mali compared to 85-90% efficacy for chloroquine in this area; 3) SP is the approved second-line antimalarial agent in Mali; and 4) its single-dose regimen ensures compliance when treatment is directly observed.