The effects on public health of climate change adaptation responses: a systematic review of evidence from low- and middle-income countries

Abstract

Climate change adaptation responses are being developed and delivered in many parts of the world in the absence of detailed knowledge of their effects on public health. Here we present the results of a systematic review of peer-reviewed literature reporting the effects on health of climate change adaptation responses in low- and middle-income countries (LMICs). The review used the 'Global Adaptation Mapping Initiative' database (comprising 1682 publications related to climate change adaptation responses) that was constructed through systematic literature searches in Scopus, Web of Science and Google Scholar (2013-2020). For this study, further screening was performed to identify studies from LMICs reporting the effects on human health of climate change adaptation responses. Studies were categorised by study design and data were extracted on geographic region, population under investigation, type of adaptation response and reported health effects. The review identified 99 studies (1117 reported outcomes), reporting evidence from 66 LMICs. Only two studies were ex ante formal evaluations of climate change adaptation responses. Papers reported adaptation responses related to flooding, rainfall, drought and extreme heat, predominantly through behaviour change, and infrastructural and technological improvements. Reported (direct and intermediate) health outcomes included reduction in infectious disease incidence, improved access to water/sanitation and improved food security. All-cause mortality was rarely reported, and no papers were identified reporting on maternal and child health. Reported maladaptations were predominantly related to widening of inequalities and unforeseen co-harms. Reporting and publication-bias seems likely with only 3.5% of all 1117 health outcomes reported to be negative. Our review identified some evidence that climate change adaptation responses may have benefits for human health but the overall paucity of evidence is concerning and represents a major missed opportunity for learning. There is an urgent need for greater focus on the funding, design, evaluation and standardised reporting of the effects on health of climate change adaptation responses to enable evidence-based policy action.

Keywords: climate change adaptation; climate change adaptation response; data synthesis; low- and middle-income countries; public health; systematic review.

Figure 1.

ROSES diagram of literature screening. Screening steps in the green coloured area were part of the GAMI, and the screening steps in the yellow area were for the current study.

Figure 2.

Heat map of the various climate drivers and health outcomes—by adaptation category: improving community resilience; policy, governance and finance; and disaster risk reduction. Several studies assessed the impact of multiple climate hazards, adaptation categories and/or health outcomes.

Figure 3.

Sankey diagram of climate hazard, adaptation responses and health outcomes. Diagram represents all individual study outcomes and data points (n = 1117) reported in the studies included in this review. (CSA = climate smart agriculture).

Figure 4.

Global distribution of included studies and their relative abundance. (The review did not cover high income countries [in grey]).

Figure 5.

Percentage of studies in each study design category for studies reporting on infectious disease, WASH and food security, as well as an all studies combined.

Figure 6.

The effect on food security indicators of climate change adaptation strategies (expressed in per cent change compared to non-adaptors or baseline measurements). Indicators related to: CONS = consumption, DD = dietary diversity, INC = income, PROD = production, FI = food insecurity; POV = poverty, RES = resilience. MIC = middle income country; LIC = low income country.