Impact,economic evaluation,and sustainability of integrated vector management in urban settings to prevent vector-borne diseases:a scoping review

Background:The control of vector-borne diseases(VBD)is one of the greatest challenges on the global health agenda.Rapid and uncontrolled urbanization has heightened the interest in addressing these challenges through an integrated vector management(IVM)approach.The aim was to identify components related to impacts,economic evaluation,and sustainability that might contribute to this integrated approach to VBD prevention.Main body:We conducted a scoping review of available literature(2000-2016)using PubMed,Web of Science,Cochrane,CINAHL,Econlit,LILACS,Global Health Database,Scopus,and Embase,as well as Tropical Diseases Bulletin,WHOLIS,WHO Pesticide Evaluation Scheme,and Google Scholar.MeSH terms and free-text terms were used.A data extraction form was used,including TIDieR and ASTAIRE.MMAT and CHEERS were used to evaluate quality.Of the 42 documents reviewed,30 were focused on dengue,eight on malaria,and two on leishmaniasis.More than a half of the studies were conducted in the Americas.Half used a quantitative descriptive approach(n=21),followed by cluster randomized controlled trials(n=11).Regarding impacts,outcomes were:a)use of measures for vector control;b)vector control;c)health measures;and d)social measures.IVM reduced breeding sites,the entomology index,and parasite rates.Results were heterogeneous,with variable magnitudes,but in all cases were favourable to the intervention.Evidence of IVM impacts on health outcomes was very limited but showed reduced incidence.Social outcomes were improved abilities and capacities,empowerment,and community knowledge.Regarding economic evaluation,only four studies performed an economic analysis,and intervention benefits outweighed costs.Costeffectiveness was dependent on illness incidence.The results provided key elements to analyze sustainability in terms of three dimensions(social,economic,and environmental),emphasizing the implementation of a community-focused eco-bio-social approach.Conclusions:IVM has an impact on reducing vector breeding sites and the entomology index,but evidence of impacts on health outcomes is limited.Social outcomes are improved abilities and capacities,empowerment,and community knowledge.Economic evaluations are scarce,and cost-effectiveness is dependent on illness incidence.Community capacity building is the main component of sustainability,together with collaboration,institutionalization,and routinization of activities.Findings indicate a great heterogeneity in the interventions and highlight the need for characterizing interventions rigorously to facilitate transferability.

Vector-borne disease and climate change adaptation in African dryland socialecological systems

Background:Drylands,which are among the biosphere's most naturally limiting and environmentally variable ecosystems,constitute three-quarters of the African continent.As a result,environmental sustainability and human development along with vector-borne disease(VBD)control historically have been especially challenging in Africa,particularly in the sub-Saharan and Sahelian drylands.Here,the VBD burden,food insecurity,environmental degradation,and social vulnerability are particularly severe.Changing climate can exacerbate the legion of environmental health threats in Africa,the social dimensions of which are now part of the international development agenda.Accordingly,the need to better understand the dynamics and complex coupling of populations and environments as exemplified by drylands is increasingly recognized as critical to the design of more sustainable interventions.Main body:This scoping review examines the challenge of vector-borne disease control in drylands with a focus on Africa,and the dramatic,ongoing environmental and social changes taking place.Dryland societies persisted and even flourished in the past despite changing climates,extreme and unpredictable weather,and marginal conditions for agriculture.Yet intrusive forces largely out of the control of traditional dryland societies,along with the negative impacts of globalization,have contributed to the erosion of dryland's cultural and natural resources.This has led to the loss of resilience underlying the adaptive capacity formerly widely exhibited among dryland societies.A growing body of evidence from studies of environmental and natural resource management demonstrates how,in light of dryland system's inherent complexity,these factors and top-down interventions can impede sustainable development and vector-borne disease control.Strengthening adaptive capacity through community-based,participatory methods that build on local knowledge and are tailored to local ecological conditions,hold the best promise of reversing current trends.Conclusions:A significant opportunity exists to simultaneously address the increasing threat of vector-borne diseases and climate change through methods aimed at strengthening adaptive capacity.The integrative framework and methods based on social-ecological systems and resilience theory offers a novel set of tools that allow multiple threats and sources of vulnerability to be addressed in combination.Integration of recent advances in vector borne disease ecology and wider deployment of these tools could help reverse the negative social and environmental trends currently seen in African drylands.