Projected impact of climate change on human health in low- and middle-income countries: a systematic review

Low- and middle-income countries (LMICs) contribute relatively little to global carbon emissions but are recognised to be among the most vulnerable parts of the world to health-related consequences of climate change. To help inform resilient health systems and health policy strategies, we sought to systematically analyse published projections of the impact of rising global temperatures and other weather-related events on human health in LMICs. A systematic search involving multiple databases was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies with modelled projections of the future impact of climate change on human health. Qualitative studies, reviews and meta-analyses were excluded. The search yielded more than 2500 articles, of which 70 studies involving 37 countries met criteria for inclusion. China, Brazil and India were the most studied countries while the sub-Saharan African region was represented in only 9% of studies. Forty specific health outcomes were grouped into eight categories. Non-disease-specific temperature-related mortality was the most studied health outcome, followed by neglected tropical infections (predominantly dengue), malaria and cardiovascular diseases. Nearly all health outcomes studied were projected to increase in burden and/or experience a geographic shift in prevalence over the next century due to climate change. Progressively severe climate change scenarios were associated with worse health outcomes. Knowledge gaps identified in this analysis included insufficient studies of various high burden diseases, asymmetric distribution of studies across LMICs and limited use of some climate parameters as independent variables. Findings from this review could be the basis for future research to help inform climate mitigation and adaptation programmes aimed at safeguarding population health in LMICs.