Identifying Vulnerable Populations in Subtropical Brisbane, Australia: A Guide for Heatwave Preparedness and Health Promotion

Building healthy societies is a key step towards climate resilient communities. Ill health is related to increased risk during heat events and is disproportionally distributed within and between communities. To understand the differences in the spatial distribution of climate related health risks and how this will change in the future we have undertaken a spatiotemporal analysis of heatwave risks in urban populations in Brisbane, Australia. The aim of this was to advise emergency managers and public health authorities of high-risk areas during extreme heat events (EHEs). The spatial distribution of heat related morbidity identified areas of high healthcare service demand during EHEs. An index of risk was developed based on social and environmental determinants of vulnerability. Regression analysis was used to determine the key drivers of heat related morbidity from the index. A weighted map of population vulnerability was produced which identified the high risk areas and provided key information to target public health interventions and heat stress prevention policy. The predicted changes in high risk populations such as the proportion of elderly people living in urban areas were also mapped to support longer term adaptation and develop health care infrastructure and health promotion strategies. 1. Introduction In Australia, heatwaves kill more people than any other natural hazard. The unequal distribution of risk between and within communities means that the elderly, the frail, and the poor experience the greatest risk. The January 2009 heatwave in south-eastern Australia resulted in the loss of hundreds of lives, disrupted power supplies and transport infrastructure, and, most importantly, placed a considerable demand on public health facilities and emergency services [1]. Vulnerability indices are useful tools to inform adaptation and increase community and organisational resilience to natural hazards such as heatwaves. Emergency managers, local governments, and public health authorities can use this approach to engage in both bottom-up and top-down adaptation strategies. When targeted heat alert systems are in place, excess mortality and morbidity during heatwaves are largely avoidable. This study has provided a “mapping tool,” the use of which will strengthen public health and emergency management policy to reduce heat-related mortality and morbidity. There is a rapidly growing body of research addressing heatwave related risk in many of the world’s larger cities, particularly in temperate and hot arid environments; less information is available