Temperature-Related Health Impacts: A Scoping Review and Benchmarking Exercise to Inform a Heat Action Plan.

Background: Global heating is associated with adverse health impacts necessitating the implementation of Heat Action Plans (HAPs) to protect communities. Gauteng in South Africa is the most populated province, housing three cities (i.e., Johannesburg, Ekurhuleni, and Pretoria) and 25% of the national population. Objective: Given rising temperatures and projected increases in heatwaves and hot days, we gathered literature and case studies to inform the development of a Gauteng HAP. Methods: We conducted a scoping review to inform baseline data on heat-related health impacts for Gauteng and South Africa too, followed by a benchmarking exercise that aimed to identify international best practices that may inform Gauteng's plan. Benchmarking was done using Maharashtra (India), Victoria (Australia), and Khyber Pakhtunkhwa (Pakistan). Findings: Thirty-six studies were included in the review, with 13 including Gauteng data and all showing impacts of heat on human health. Most studies applied epidemiological time series linking meteorological exposure (temperature/heat indices) and/or air pollutants (e.g., PM2.5, PM10, NO2, and O3) with health outcomes; applied remote-sensing, reanalysis, or station data for exposure assessment; and used regression or distributed lag models. The benchmarking exercise identified exemplars' distinctive strengths: Victoria's district thresholds keep activation simple and local-ideal for Gauteng's heterogeneous microclimates across metros and townships. Maharashtra's graded activation and clear departmental roles reduce ambiguity during multi-day heatwaves and thereby would help to align Gauteng Health, Infrastructure, Social Development departments. Khyber Pakhtunkhwa's cooling-camp model shows practical, low-cost interventions of a low- and middle-income country that can be replicated at taxi ranks/clinics/malls during temperature peaks. Conclusions: Insights from the literature and international exemplars provide a strong evidence base and adaptable models to guide a context-specific, multi-sectoral HAP for Gauteng that enhances preparedness, coordination, and community protection in a warming South Africa.