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Despite a significant reduction in the burden of malaria in children under five years-old, the efficient implementation of seasonal malaria chemoprevention (SMC) at large scale remains a major concern in areas with long malaria transmission. Low coverage rate in the unattainable areas during the rainy season, a shift in the risk of malaria to older children and the rebound in malaria incidence after stopping drug administration are mainly reported in these areas. These gaps represent a major challenge in the efficient implementation of SMC measures. An open randomized study was conducted to assess the effect of a fifth additional round to current regime of SMC in older children living in Dangassa, a rural malaria endemic area. Poisson regression Model was used to estimate the reduction in malaria incidence in the intervention group compared to the control group including age groups (5-9 and 10-14 years) and the use of long-lasting insecticidal nets (LLINs; Yes or No) with a threshold at 5%. Overall, a downward trend in participation rate was observed from August (94.3%) to November (87.2%). In November (round 4), the risk of malaria incidence was similar in both groups (IRR = 0.66, 95%CI [0.35-1.22]). In December (round 5), a decrease of 51% in malaria incidence was observed in intervention group compared to control group adjusted for age groups and the use of LLINs (IRR = 0.49, 95%CI [0.26-0.94]), of which 17% of reduction is attributable to the 5th round in the intervention group. An additional fifth round of SMC resulted in a significant reduction of malaria incidence in the intervention group. The number of SMC rounds could be adapted to the local condition of malaria transmission.

BackgroundAttractive targeted sugar baits (ATSBs) are a promising new tool for malaria control as they can target outdoor-feeding mosquito populations, in contrast to current vector control tools which predominantly target indoor-feeding mosquitoes.MethodsIt was sought to estimate the potential impact of these new tools on Plasmodium falciparum malaria prevalence in African settings by combining data from a recent entomological field trial of ATSBs undertaken in Mali with mathematical models of malaria transmission. The key parameter determining impact on the mosquito population is the excess mortality due to ATSBs, which is estimated from the observed reduction in mosquito catch numbers. A mathematical model capturing the life cycle of P. falciparum malaria in mosquitoes and humans and incorporating the excess mortality was used to estimate the potential epidemiological effect of ATSBs.ResultsThe entomological study showed a significant reduction of ~ 57% (95% CI 33-72%) in mosquito catch numbers, and a larger reduction of ~ 89% (95% CI 75-100%) in the entomological inoculation rate due to the fact that, in the presence of ATSBs, most mosquitoes do not live long enough to transmit malaria. The excess mortality due to ATSBs was estimated to be lower (mean 0.09 per mosquito per day, seasonal range 0.07-0.11 per day) than the bait feeding rate obtained from one-day staining tests (mean 0.34 per mosquito per day, seasonal range 0.28-0.38 per day).ConclusionsFrom epidemiological modelling, it was predicted that ATSBs could result in large reductions (> 30% annually) in prevalence and clinical incidence of malaria, even in regions with an existing high malaria burden. These results suggest that this new tool could provide a promising addition to existing vector control tools and result in significant reductions in malaria burden across a range of malaria-endemic settings.

BackgroundModerate acute malnutrition (MAM) affects 34.1 million children globally. Treatment effectiveness is generally determined by the amount and rate of weight gain. Body composition (BC) assessment provides more detailed information on nutritional stores and the type of tissue accrual than traditional weight measurements alone.ObjectiveThe aim of this study was to compare the change in percentage fat mass (%FM) and other BC parameters among young Malian children with MAM according to receipt of 1 of 4 dietary supplements, and recovery status at the end of the 12-wk intervention period.MethodsBC was assessed using the deuterium oxide dilution method in a subgroup of 286 children aged 6-35 mo who participated in a 12-wk community-based, cluster-randomized effectiveness trial of 4 dietary supplements for the treatment of MAM: 1) lipid-based, ready-to-use supplementary food (RUSF); 2) special corn-soy blend "plus plus" (CSB++); 3) locally processed, fortified flour (MI); or 4) locally milled flours plus oil, sugar, and micronutrient powder (LMF). Multivariate linear regression modeling was used to evaluate change in BC parameters by treatment group and recovery status.ResultsMean ± SD %FM at baseline was 28.6% ± 5.32%. Change in %FM did not vary between groups. Children who received RUSF vs. MI gained more (mean; 95% CI) weight (1.43; 1.13, 1.74 kg compared with 0.84; 0.66, 1.03 kg; P = 0.02), FM (0.70; 0.45, 0.96 kg compared with 0.20; 0.05, 0.36 kg; P = 0.01), and weight-for-length z score (1.23; 0.79, 1.54 compared with 0.49; 0.34, 0.71; P = 0.03). Children who recovered from MAM exhibited greater increases in all BC parameters, including %FM, than children who did not recover.ConclusionsIn this study population, children had higher than expected %FM at baseline. There were no differences in %FM change between groups. International BC reference data are needed to assess the utility of BC assessment in community-based management of acute malnutrition programs. This trial was registered at clinicaltrials.gov as NCT01015950.

BackgroundEarly screening is crucial for early autism spectrum disorders (ASD) diagnosis and intervention. ASD screening tools have mostly been constructed based on the Western cultural context. We hypothesized that their use in Mali may require a prior validation.ObjectiveTo validate the modified checklist for autism in toddlers-Revised (M-CHAT-R) and the social communication questionnaire (SCQ) in the Malian sociocultural context for ASD screening.Study designWe administered M-CHAT-R and SCQ in 947 toddlers aged 16-30 months old at the district and community health centers in Bamako and 120 patients (60 autistic and 60 age and sex matched controls) aged ≥4 years old at the psychiatry department in Bamako. Toddlers at moderate to high risk of ASD underwent M-CHAT-R/F and clinical evaluation by an ASD multidisciplinary team. M-CHAT-R and SCQ were evaluated for cultural appropriateness by Malian anthropologists. The sensitivity, specificity, PPV, NPV were determined for both M-CHAT-R and SCQ. Health professionals have been trained during ASD seminary on how to use M-CHAT-R and SCQ for ASD screening in Bamako.ResultsWe found for the M-CHAT-R a sensitivity of 50%, a specificity of 100%, a PPV of 100% and a NPV of 87%. The SCQ had a sensitivity of 71%, a specificity of 72%, a PPV of 73% and a NPV of 70%. We have found four out of 20 items on the M-CHAT-R that were culturally inappropriate in the Malian context.DiscussionM-CHAT-R and SCQ can be used for early autism screening in Mali. In the future, we plan to train a descent number of Malian physicians in chief and pediatricians at the district hospitals across the country to integrate the early ASD screening into the national health system.ConclusionM-CHAT-R has a perfect specificity and SCQ a fair diagnostic accuracy for ASD in Mali.

IntroductionModerate acute malnutrition (MAM) causes substantial child morbidity and mortality, accounting for 4.4% of deaths and 6.0% of disability-adjusted life years (DALY) lost among children under 5 each year. There is growing consensus on the need to provide appropriate treatment of MAM, both to reduce associated morbidity and mortality and to halt its progression to severe acute malnutrition. We estimated health outcomes, costs and cost-effectiveness of four dietary supplements for MAM treatment in children 6-35 months of age in Mali.MethodsWe conducted a cluster-randomised MAM treatment trial to describe nutritional outcomes of four dietary supplements for the management of MAM: ready-to-use supplementary foods (RUSF; PlumpySup); a specially formulated corn-soy blend (CSB) containing dehulled soybean flour, maize flour, dried skimmed milk, soy oil and a micronutrient pre-mix (CSB++; Super Cereal Plus); Misola, a locally produced, micronutrient-fortified, cereal-legume blend (MI); and locally milled flour (LMF), a mixture of millet, beans, oil and sugar, with a separate micronutrient powder. We used a decision tree model to estimate long-term outcomes and calculated incremental cost-effectiveness ratios (ICERs) comparing the health and economic outcomes of each strategy.ResultsCompared to no MAM treatment, MAM treatment with RUSF, CSB++, MI and LMF reduced the risk of death by 15.4%, 12.7%, 11.9% and 10.3%, respectively. The ICER was US$9821 per death averted (2015 USD) and US$347 per DALY averted for RUSF compared with no MAM treatment.ConclusionMAM treatment with RUSF is cost-effective across a wide range of willingness-to-pay thresholds.Trial registrationNCT01015950.

BackgroundResidual malaria transmission has been reported in many areas even with adequate indoor vector control coverage, such as long-lasting insecticidal nets (LLINs). The increased insecticide resistance in Anopheles mosquitoes has resulted in reduced efficacy of the widely used indoor tools and has been linked with an increase in outdoor malaria transmission. There are considerations of incorporating outdoor interventions into integrated vector management (IVM) to achieve malaria elimination; however, more information on the combination of tools for effective control is needed to determine their utilization.MethodsA spatial individual-based model was modified to simulate the environment and malaria transmission activities in a hypothetical, isolated African village setting. LLINs and outdoor attractive toxic sugar bait (ATSB) stations were used as examples of indoor and outdoor interventions, respectively. Different interventions and lengths of efficacy periods were tested. Simulations continued for 420 days, and each simulation scenario was repeated 50 times. Mosquito populations, entomologic inoculation rates (EIRs), probabilities of local mosquito extinction, and proportion of time when the annual EIR was reduced below one were compared between different intervention types and efficacy periods.ResultsIn the village setting with clustered houses, the combinational intervention of 50% LLINs plus outdoor ATSBs significantly reduced mosquito population and EIR in short term, increased the probability of local mosquito extinction, and increased the time when annual EIR is less than one per person compared to 50% LLINs alone; outdoor ATSBs alone significantly reduced mosquito population in short term, increased the probability of mosquito extinction, and increased the time when annual EIR is less than one compared to 50% LLINs alone, but there was no significant difference in EIR in short term between 50% LLINs and outdoor ATSBs. In the village setting with dispersed houses, the combinational intervention of 50% LLINs plus outdoor ATSBs significantly reduced mosquito population in short term, increased the probability of mosquito extinction, and increased the time when annual EIR is less than one per person compared to 50% LLINs alone; outdoor ATSBs alone significantly reduced mosquito population in short term, but there were no significant difference in the probability of mosquito extinction and the time when annual EIR is less than one between 50% LLIN and outdoor ATSBs; and there was no significant difference in EIR between all three interventions. A minimum of 2 months of efficacy period is needed to bring out the best possible effect of the vector control tools, and to achieve long-term mosquito reduction, a minimum of 3 months of efficacy period is needed.ConclusionsThe results highlight the value of incorporating outdoor vector control into IVM as a supplement to traditional indoor practices for malaria elimination in Africa, especially in village settings of clustered houses where LLINs alone is far from sufficient.

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BackgroundAs malaria prevalence declines in many parts of the world due to widescale control efforts and as drug-resistant parasites begin to emerge, a quantitative understanding of human movement is becoming increasingly relevant to malaria control. However, despite its importance, significant knowledge gaps remain regarding human movement, particularly in sub-Saharan Africa.MethodsA quantitative survey of human movement patterns was conducted in four countries in sub-Saharan Africa: Mali, Burkina Faso, Zambia, and Tanzania, with three to five survey locations chosen in each country. Questions were included on demographic and trip details, malaria risk behaviour, children accompanying travellers, and mobile phone usage to enable phone signal data to be better correlated with movement. A total of 4352 individuals were interviewed and 6411 trips recorded.ResultsA cluster analysis of trips highlighted two distinct traveller groups of relevance to malaria transmission: women travelling with children (in all four countries) and youth workers (in Mali). Women travelling with children were more likely to travel to areas of relatively high malaria prevalence in Mali (OR = 4.46, 95% CI = 3.42-5.83), Burkina Faso (OR = 1.58, 95% CI = 1.23-1.58), Zambia (OR = 1.50, 95% CI = 1.20-1.89), and Tanzania (OR = 2.28, 95% CI = 1.71-3.05) compared to other travellers. They were also more likely to own bed nets in Burkina Faso (OR = 1.77, 95% CI = 1.25-2.53) and Zambia (OR = 1.74, 95% CI = 1.34 2.27), and less likely to own a mobile phone in Mali (OR = 0.50, 95% CI = 0.39-0.65), Burkina Faso (OR = 0.39, 95% CI = 0.30-0.52), and Zambia (OR = 0.60, 95% CI = 0.47-0.76). Malian youth workers were more likely to travel to areas of relatively high malaria prevalence (OR = 23, 95% CI = 17-31) and for longer durations (mean of 70 days cf 21 days, p < 0.001) compared to other travellers.ConclusionsWomen travelling with children were a remarkably consistent traveller group across all four countries surveyed. They are expected to contribute greatly towards spatial malaria transmission because the children they travel with tend to have high parasite prevalence. Youth workers were a significant traveller group in Mali and are expected to contribute greatly to spatial malaria transmission because their movements correlate with seasonal rains and hence peak mosquito densities. Interventions aimed at interrupting spatial transmission of parasites should consider these traveller groups.

Background: The diagnosis of tuberculosis (TB) has mostly been relied on a long-used method called sputum smear microscopy. In 2010, Xpert MTB/RIF assay was approved by the World Health Organization for simultaneous TB diagnosis and detection of resistance. Our current study was undertaken to compare the diagnostic performance of Xpert MTB/RIF assay to auramine staining-based light-emitting diode-Fluorescence Microscopy (LED-FM) considering culture as the gold standard method for pulmonary and extrapulmonary TB. Method: Pulmonary and extrapulmonary specimens of suspected TB patients were examined in this study. From January 2016 to June 2019, sputum, urine, superficial swabs, gastric aspirates, and pleural infusion specimens were collected from new and previously treated TB individuals. Specimens were examined using Xpert MTB/RIF, LED-FM, and Mycobacterium culture techniques to evaluate their performance. Results: A total of 697 suspected TB samples were included in this analysis, and of these, 469 (67.29%) were positive for all three used methods. The overall sensitivities, specificities, and positive and negative predictive values were 99.6%, 62.0%, 88.4%, and 98.2% for Xpert MTB/RIF and 88.0%, 95.6%, 99.0%, and 60.7% for LED-FM, respectively, compared to culture method. Conclusion: The sensitivity of Xpert MTB/RIF assay was observed to be higher than the LED-FM method, thus suggesting this molecular technique as a promising tool for the diagnosis of pulmonary and extrapulmonary TB, which will help in the management of TB infections in developing countries such as Mali.

Objectives New international guidelines for antenatal care (ANC) will likely result in an increase in nutritional supplements and preventative medications for pregnant women in low and middle-income countries. Our objective was to understand how pregnant women in Mali perceive and experience multi-drug regimens in ANC in order to reveal factors that may influence uptake and adherence. Methods We conducted 29 semi-structured interviews and three focus groups with 21 pregnant women in two urban ANC sites in Bamako, Mali. Interviews focused on perception of purpose of ANC pharmaceuticals (particularly iron supplements, sulfadoxine-pyrimethamine as intermittent prevention of malaria and antiretroviral therapy for HIV), beliefs regarding efficacy and risk, and understanding of dosage and regimen. Transcripts were inductively coded and analyzed using the 'Framework' method. Results Participant descriptions of medication purpose, understanding of dosing, and beliefs about risks and efficacy varied widely, revealing that many pregnant women lack complete information about their medications. While some were burdened by side effects or complex regimens, women generally held favorable attitudes toward ANC medications. Responses suggest major barriers to adherence lie in the health system, namely insufficient patient-provider communication and inconsistent prescribing practices. Conclusions for Practice National health programs looking to improve maternal and child health with ANC pharmaceuticals need to place greater attention on patient counseling and consistent implementation of administration guidelines. Communication that positions pharmaceuticals as beneficial to mother and child, while presenting understandable information about purpose, dosing and potential side effects can promote uptake of multi-drug regimens and ANC services in general., Author(s): Alexandra R. Searle [sup.1] , Emily A. Hurley [sup.1] [sup.2] , Seydou O. Doumbia [sup.3] , Peter J. Winch [sup.1] Author Affiliations: (1) grid.21107.35, 0000 0001 2171 9311, Department [...]

BackgroundThe development of insecticide resistance and the increased outdoor-biting behaviour of malaria vectors reduce the efficiency of indoor vector control methods. Attractive toxic sugar baits (ATSBs), a method targeting the sugar-feeding behaviours of vectors both indoors and outdoors, is a promising supplement to indoor tools. The number and configuration of these ATSB stations needed for malaria control in a community needs to be determined.MethodsA hypothetical village, typical of those in sub-Saharan Africa, 600 × 600 m, consisting of houses, humans and essential resource requirements of Anopheles gambiae (sugar sources, outdoor resting sites, larval habitats) was simulated in a spatial individual-based model. Resource-rich and resource-poor environments were simulated separately. Eight types of configurations and different densities of ATSB stations were tested. Anopheles gambiae population size, human biting rate (HBR) and entomological inoculation rates (EIR) were compared between different ATSB configurations and densities. Each simulated scenario was run 50 times.ResultsCompared to the outcomes not altered by ATSB treatment in the control scenario, in resource-rich and resource-poor environments, respectively, the optimum ATSB treatment reduced female abundance by 98.22 and 91.80 %, reduced HBR by 99.52 and 98.15 %, and reduced EIR by 99.99 and 100 %. In resource-rich environments, n × n grid design, stations at sugar sources, resting sites, larval habitats, and random locations worked better in reducing vector population and HBRs than other configurations (P < 0.0001). However, there was no significant difference of EIR reductions between all ATSB configurations (P > 0.05). In resource-poor environments, there was no significant difference of female abundances, HBRs and EIRs between all ATSB configurations (P > 0.05). The optimum number of ATSB stations was about 25 for resource-rich environments and nine for resource-poor environments.ConclusionsATSB treatment reduced An. gambiae population substantially and reduced EIR to near zero regardless of environmental resource availability. In resource-rich environments, dispersive configurations worked better in reducing vector population, and stations at or around houses worked better in preventing biting and parasite transmission. In resource-poor environments, all configurations worked similarly. Optimum numbers of bait stations should be adjusted according to seasonality when resource availability changes.

BackgroundAgent-based modelling (ABM) has been used to simulate mosquito life cycles and to evaluate vector control applications. However, most models lack sugar-feeding and resting behaviours or are based on mathematical equations lacking individual level randomness and spatial components of mosquito life. Here, a spatial individual-based model (IBM) incorporating sugar-feeding and resting behaviours of the malaria vector Anopheles gambiae was developed to estimate the impact of environmental sugar sources and resting sites on survival and biting behaviour.MethodsA spatial IBM containing An. gambiae mosquitoes and humans, as well as the village environment of houses, sugar sources, resting sites and larval habitat sites was developed. Anopheles gambiae behaviour rules were attributed at each step of the IBM: resting, host seeking, sugar feeding and breeding. Each step represented one second of time, and each simulation was set to run for 60 days and repeated 50 times. Scenarios of different densities and spatial distributions of sugar sources and outdoor resting sites were simulated and compared.ResultsWhen the number of natural sugar sources was increased from 0 to 100 while the number of resting sites was held constant, mean daily survival rate increased from 2.5% to 85.1% for males and from 2.5% to 94.5% for females, mean human biting rate increased from 0 to 0.94 bites per human per day, and mean daily abundance increased from 1 to 477 for males and from 1 to 1,428 for females. When the number of outdoor resting sites was increased from 0 to 50 while the number of sugar sources was held constant, mean daily survival rate increased from 77.3% to 84.3% for males and from 86.7% to 93.9% for females, mean human biting rate increased from 0 to 0.52 bites per human per day, and mean daily abundance increased from 62 to 349 for males and from 257 to 1120 for females. All increases were significant (P < 0.01). Survival was greater when sugar sources were randomly distributed in the whole village compared to clustering around outdoor resting sites or houses.ConclusionsIncreases in densities of sugar sources or outdoor resting sites significantly increase the survival and human biting rates of An. gambiae mosquitoes. Survival of An. gambiae is more supported by random distribution of sugar sources than clustering of sugar sources around resting sites or houses. Density and spatial distribution of natural sugar sources and outdoor resting sites modulate vector populations and human biting rates, and thus malaria parasite transmission.