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Anopheles coluzzii and An. gambiae—the two most recently radiated species of the An. gambiae complex and the major Afrotropical malaria vector species—are identified by markers in the X-centromeric IGS rDNA region. Putative IGS-hybrids are rarely found in the field, except in restricted areas where genomic studies have led to the hypothesis that the observed IGS-patterns are due to cryptic taxa rather than to hybridization between the two species. We investigated the genome-wide levels of admixture in two villages in Côte d’Ivoire where high levels of IGS-hybrids have been detected, confirming unparalleled high frequencies in the coastal village. Genotyping of 24 Ancestry Informative Markers (AIMs) along the three chromosomes produced discordant results between the IGS-marker and the multilocus genotype obtained for AIMs across the whole genome (29%) as well as AIMs on chromosome-X (considered to be fundamental for species reproductive isolation) only (21%). Results highlight a complicated pattern of admixture that deserves deeper genomic analyses to understand better possible underlying causes (from extensive processes of hybridization to the existence of different cryptic taxa), and stress the need of developing advanced diagnostics for An. coluzzii, An. gambiae and putative new taxa, instrumental for assessing taxon-specific epidemiological characters.

BACKGROUND Even though climate change is one of the most significant global health challenges, empirical population-based data on its impacts and adaptation measures to protect population health are still limited. The 56 long-term health cohorts in Africa and Asia, called Health and Demographic Surveillance Systems (HDSSs) are excellent for monitoring climate impact on health and adaptation measures as they: (i) follow quality controlled protocols of data collection across all sites, (ii) provide long-term continuous data, (iii) cover diverse climate hotspots, including coastal areas, rainforests, savannah and highlands, and, (iv) capture about 100-million-person years of data. However, HDSSs have not leveraged their potential for climate and health research and policy, as (i) local meteorological data or remotely sensed data is not incorporated; (ii) there are limited links to downscaled climate impact models for HDSSs; (iii) and at its core, demographic dynamics are captured, with cause of death being the major health indicator tracked over time. OBJECTIVE We introduced major improvements in data collection, database architecture, data transmission, as well as links to locally downsized climate models to capitalize on the strong potential of HDSSs sites for measuring health impacts of climate change, identifying particularly vulnerable groups, and testing the costs and effectiveness of adaptation interventions and policies to protect populations from these climate impacts. This bundle of methods called Climate and Health Surveillance and Response System (CHES-RS) aims to provide a consistent set of climate and health data which are routinely collected. METHODS The CHES-RS has already been piloted in the HDSS at the Nouna Health Research Center in Burkina Faso, and it is currently being rolled out to two other HDSS sites, one in sub-Saharan Africa, respectively in the Siaya HDSS, Kenya, and the other in the South East Asia Community Observatory (SEACO) HDSS in Malaysia. CHES-RSs are ready to conduct research in the following major health sectors: climate/weather, land use and coverage/biodiversity, agriculture/household harvest, food security, household economics, as well as research in the field of one health, including zoonotic disease surveillance. CHES-RS uses digital sensors to measure three levels of exposure: (i) Individual-level data: consumer-grade wearable devices yield objective measures in vulnerable and rural populations, and an expanded HDSS questionnaire includes a full morbidity evaluation (ii) Household-level data comprises both indoor temperature measurements and remote sensing data captured through satellites (iii) Community-level data: comes from fully automated weather stations that record temperature, precipitation, solar radiation, wind speed, and direction. To handle heterogeneous data, we leverage graph databases for data management. RESULTS NA CONCLUSIONS To address current and emerging global health challenges over the next few decades, CHES-RSs will serve as a novel architecture for existing HDSSs and similar infrastructures of population-based surveillance cohorts. They may encourage ecosystems for climate change and health research, as well as big data analysis using artificial intelligence (AI), potentially providing the foundation for calculating climate change-induced disability-adjusted life years (cDALYs) and loss and damages. Using a routine morbidity panel survey and objectively measured health data, CHES-RS generate data-rich cohorts in countries where good quality health data is scarce, allowing for early interventions and earlier detection of risk factors for illnesses.

The first line of malaria vector control to date mainly relies on the use of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS). For integrated vector management, targeting the vector larvae with biological larvicides such as Bacillus thuringiensis israelensis (Bti) can be an effective additional mainstay. This study presents data from the second intervention year of a large-scale trial on biological larviciding with Bti that was carried out in 127 rural villages and a semi-urban town in Burkina Faso. Here we present the reductions in malaria mosquitoes that were achieved by continuing the initial interventions for an additional year, important to assess sustainability and repeatability of the results from the first intervention year. Larviciding was performed applying two different larviciding choices ((a) treatment of all environmental breeding sites, and (b) selective treatment of those that were most productive for Anopheles larvae indicated by remote sensing based risk maps). Adult Anopheles spp. mosquito abundance was reduced by 77.4% (full treatment) and 63.5% (guided treatment) compared to the baseline year. The results showed that malaria vector abundance can be dramatically reduced using biological larviciding and that this effect can be achieved and maintained over several consecutive transmission seasons.

Additional file 5:. Table 4 Percentage of 523 children aged

Additional file 3: Table 2 Rotated factor loadings of food items for the four identified dietary pattern scores among children aged

Additional file 6: Table 5 Characteristics and frequencies of food intake of children aged

Additional file 7:. Table 6 Sensitivity analyses of associations of DDS, FVS, and four DPS with stunting (HAZ

Additional file 1:. Table 1 Overview of food groups and food items.

Additional file 8:. Table 7: Sensitivity analyses of associations of DDS, FVS and four DPS with wasting (WHZ

Additional file 2:. Figure 1 Scree plot of eigenvalues after factor analysis to derive dietary patterns.

Additional file 4:. Table 3 Percentage of 523 children aged

Background Knowing which dietary habits are associated with child growth could lead to better long-term health outcomes and improve the design of food-based interventions. We aimed to identify dietary habits that are associated with the growth development of children aged Methods This study used cross-sectional baseline data from 514 children (8–59 months) within the Nouna Health and Demographic Surveillance System (HDSS) in 2018. Household socio-demographics and child dietary habits, height and weight were assessed. We constructed scores for dietary diversity (DDS) and food variety (FVS), and extracted exploratory dietary pattern scores (DPS) using principal component analysis (PCA). Child growth was measured using height-for-age (HAZ) and weight-for-height z-scores (WHZ). We used multiple-adjusted linear regressions considering for socio-economic factors to quantify associations. Results In this study population (median 36 ± 14 months old), stunting (HAZ Conclusion Growth development of children aged

Background: Malaria remains one of the most important causes of morbidity and death in Sub-Saharan Africa. Along with early diagnosis and treatment of malaria cases and intermittent preventive treatment in pregnancy (IPTp), vector control is an important tool in the reduction of new cases. Alongside the use of long lasting insecticide treated bed nets (LLINs) and indoor residual spraying (IRS), targeting the vector larvae with biological larvicides such as Bacillus thuringiensis israelensis (Bti) is gaining importance as a means of reducing the number of mosquito larvae before they emerge to their adult stage. With this study, we present data corroborating the entomological impact of such an intervention in a rural African environment. Methods: The study extended over two years and researched the impact of biological larviciding with Bti on malaria mosquitoes that were caught indoors and outdoors of houses using light traps. We calculated the achieved reductions in female Anopheles mosquitoes for two different larviciding choices using a regression model. Findings: In villages that received selective treatment of the most productive breeding sites, the number of female Anopheles spp. dropped by 61% (95% CI: 54%-66%) compared to the pre-intervention period. In villages in which all breeding sites were treated, the number of female Anopheles spp. was reduced by 70% (95% CI: 64%-74%) compared to the pre-intervention period. Interpretation: We showed that malaria vector abundance can be dramatically reduced through larviciding of breeding habitats and that, in many geographical settings, they are a viable addition to current malaria control measures. Trial Registration Information: The study was registered under the trial id PACTR201611001721299 on the Pan African Clinical Trials Registry.. Funding Statement: This work was financed by Manfred Lautenschlager foundation, Wiesloch, Germany. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The study was approved by the ethics committees of the University of Heidelberg under the certificate number S-438/2013 and additionally presented to and granted by the national ethics board of Burkina Faso in Ouagadougou and the local ethics committee at the research site in Nouna. We collected aggregated collective informed consent for the spraying activities for each village.

Background: Recent malaria control and elimination attempts show remarkable success in several parts of sub-Saharan Africa. Vector control via larval source management represents a new and to date underrepresented approach in low income countries to further reduce malaria transmission. Although the positive impact of such campaigns on malaria incidence has been researched, there is a lack of data on which prerequisites are needed for implementing such programs on a routine basis on large scale. Our objectives are to point out important steps in implementing an anti-malaria larviciding campaign in a resource and infrastructure restraint setting and share the lessons learned from our experience during a three-year intervention study in rural Burkina Faso. Methods: We describe the approaches we followed and the challenges that have been encountered during the EMIRA project, a three-year study on the impact of environmental larviciding on vector ecology and human health. An inventory of all performed work packages and associated problems and peculiarities was assembled. Results: Key to the successful implementation of the larviciding program within a health district was the support and infrastructure from the local research center run by the government. This included availability of trained scientific personnel for local project management, data collection and analysis by medical personnel, entomologists and demographers and teams of fieldworkers for the larviciding intervention. A detailed a priori assessment of the environment and vector breeding site ecology was essential to calculate personnel requirements and the need for larvicide and application apparel. In our case of a three-year project, solid funding for the whole duration was an important issue, which restricted the number of possible donors. We found the acquisition of qualified field personnel in fair numbers not to be always easy and training in application techniques and basic entomologic knowledge required several weeks of theoretical and practical formation. A further crucial point was to establish an effective quality control system that ensured the timely verification of larviciding success and facilitated in time data handling. While the experiences of running a larviciding campaign may vary globally, the experiences gained and the methods used in the Nouna health district may be employed in similar settings. Conclusions: Our observations highlight important components and strategies that should be taken into account when planning and running a similar larviciding program against malaria in a resource limited setting. A strong local partnership, meticulous planning with the possibility of ad-hoc adaption of project components and a reliable source of funding turned out to be crucial factors to successfully accomplish such a project.

English translation of the interview guide used to direct discussions. The interview guide used in the field is in French language. (DOCX 12 kb)

This paper describes a model for the simulation of the information diffusion impacts on the spread of meningitis in West-Africa. The approach is based on agent-based modeling to represent explicitly (1) the relationships and interactions among individuals through their social networks and (2) the spread of the disease at individual and system level. The model is applied to explore the impacts of the structure of social networks and the trust distribution on the information diffusion and the spread of the meningitis disease.

ObjectiveWe investigated the association between junk food consumption at lunchtime (JCL) and fast-food outlet access near school among secondary-school children in Quebec.DesignA geographic information system database was used to characterize the food environment around a sub-sample of 374 public schools in which 26 655 students were enrolled. The outcome variable was JCL during the previous week, dichotomized into low JCL (none or once)v. high JCL (twice or more). Access to fast-food outlets near school was assessed using an existing database of fast-food outlets in Quebec. Covariates included student (age, sex and self-rated perceived health), family (familial status and parental education) and school (urban/rural status and deprivation) variables. Hierarchical logistic regression models were employed for analyses using PROC GLIMMIX of SAS version 9.3.SettingProvince of Quebec, Canada.SubjectsWe used data from the Quebec Health Survey of High School Students (QHSHSS) 2010–11, a survey of secondary-school Quebec students.ResultsExposure to two or more fast-food outlets within a radius of 750 m around schools was associated with a higher likelihood of excess JCL (OR=1·50; 95 % CI 1·28, 1·75), controlling for the characteristics of the students, their families and their schools.ConclusionsThe food environment surrounding schools can constitute a target for interventions to improve food choices among secondary-school children living in the province of Quebec. Transforming environments around schools to promote healthy eating includes modifying zoning regulations that restrict access to fast-food outlets around schools.

Additional file 1: Table S1. Total accrued costs in US$ for the EMIRA research project. Calculations based on 2013 costs for material and personnel using a 2013–2015 average exchange rate of US$ 1 = € 0.82.

Background : Malaria control is based on early treatment of cases and on vector control. The current measures for malaria vector control in Africa are mainly based on long-lasting insecticide treated nets (LLINs) and to a much smaller extent on indoor residual spraying (IRS). A third pillar in the fight against the malaria vector, larval source management (LSM), has virtually not been used in Africa since the ban of DDT in the 1960s. Within the light of recent WHO recommendations for Bacillus thuringiensis israelensis ( Bti ) use against malaria and other vector species, larval source management could see a revival in the upcoming years. In this project we analyze the ecologic and health impacts as well as the cost effectiveness of larval source management under different larviciding scenarios in a health district in Burkina Faso. Methods : The project is designed as prospective intervention study with duration of three years (2013–2015). Its spatial scale includes three arms of interventions and control, comprising a total of 127 villages and the district capital Nouna in the extended HDSS (Health Demographic Surveillance System) of the Kossi province. Baseline data on mosquito abundance, parasitemia in U5 children, and malaria related morbidity and mortality are gathered over the project duration. Besides the outcome on ecologic and health parameters, the economic costs are seized and valued against the achieved health benefits. Conclusions : Risk map based, guided larvicide application might be a possibility to further decrease economic cost of LSM and facilitate its faster incorporation to integrated malaria control programs. Given the limited resources in many malaria endemic countries, it is of utmost importance to relate the costs of novel strategies for malaria prevention to their effect on the burden of the disease. Occurring costs and the impact on the health situation will be made comparable to other, existing intervention strategies, allowing stakeholders and policymakers decision making. Keywords : Malaria; Bacillus thuringiensis israelensis; vector control; study design; larval source management; Burkina Faso (Published: 5 November 2014) Citation : Glob Health Action 2014, 7 : 25908 - http://dx.doi.org/10.3402/gha.v7.25908

Background Identification and better understanding of potential risk factors for malaria are important for targeted and cost-effective health interventions. Housing conditions have been suggested as one of the potential risk factors. This study aims to further investigate this risk factor, and is focused on the effect of the type of roof on Plasmodium falciparum infection among children below five years in the North West of Burkina Faso. Methods In a cross-sectional study design, 661 children aged six to 60 months were randomly selected from three rural and one semi-urban site at the end of the rainy season (November 2003). The children were screened for fever and tested for Plasmodium falciparum infection. In addition, data on bed net use and house characteristics was collected from the household were each child lived. Using adjusted odds ratios, children living in house roofed with iron-sheet were compared with those in house with mud or grass roof. Results Overall P. falciparum infection prevalence was 22.8 % with a significant variation between (Chi-square, p < 0.0001). The prevalence in Cissé (33.3 %) and Goni (30.6 %) were twice times more than in Nouna (15.2 %) and Kodougou (13.2 %). After adjusting for age, sex, use of bed net and housing conditions, children living in houses with mud roofs had significantly higher risk of getting P. falciparum infection compared to those living in iron-sheet roofed houses (Odds Ratio 2.6; 95% Confidence Interval, 1.4–4.7). Conclusion These results suggest that house characteristics should be taken into consideration when designing health intervention against P. falciparum infection and particular attention should be paid to children living in houses with mud roofs.