Health and migration in the context of a changing climate: a systematic literature assessment

Abstract
Background: Climate change and climate variability interact with political, economic, social, demographic and other environmental drivers to change the scale and patterns of human migration. In the context of accelerating climate change and breaches to other planetary boundaries, there is an urgent need to better understand how migrant health can be protected and promoted in the context of a changing climate in order to manage safe and orderly migration2. While research has focused on the separate dyads of i) climate change and migration and ii) climate change and health, limited consideration has been given to the nexus between climate change, migration, and health. This review synthesizes research that has investigated this relationship since 1990. Methods: Following an a priori protocol and with the assistance of a subject librarian, systematic searches were conducted in four academic databases (PubMed, Scopus, Ovid Medline, and Global Health) and Google Scholar for empirical studies investigating migration and health in the context of climate change with any study design between 1990 - 2018. The search results underwent a two-stage screening process and the eligible studies were subjected to quality appraisal using a mixed methods appraisal tool. Data extraction and a meta-synthesis followed producing outputs deemed most useful for policy, practice and further research. Findings: The registered protocol and search strategy revealed 1,904 studies of which 180 were screened in full- text and 50 were appraised for quality and subsequently included in the meta-synthesis. The review produced five main findings: 1) there is a paucity of empirical research investigating the climate-health-migration nexus; 2) the relationships between migration and health in the context of climate change are strongly heterogeneous and global findings are unlikely to emerge; 3) studies have examined diverse health issues associated with migration in the context of climate change including changing patterns of infectious disease, non-communicable disease, psychosocial conditions, and access to health care; 4) food and water security are important mediators between climate change, human mobility and health outcomes; 5) there is no consistent approach to integrating climate data in studies exploring migration and health in the context of climate change.