Abstract
<title>Abstract</title> <p>Heat-related illnesses (HRI) are a growing public health concern in our warming world. Timely treatment is critical but early recognition and management of secondary complications remains challenging due to the heterogeneous nature of its clinical presentation. We present the Heat Illness Avatar (HIA), an open interactive digital resource developed from 610 clinically diagnosed exertional HRI cases reported across 248 studies. The HIA integrates data from diverse exertional contexts, climates, and geographic locations, encompassing patients with varied demographics, disease severity, and clinical outcomes. As an open-access resource and clinical decision-support tool, it enables generation of reference HRI phenotypes, quantification of frequency and mortality risk across 588 clinical features, and stratification by user-defined variables including age, environment, activity, and exercise intensity. These capabilities establish the HIA as an integrated platform to support future research and to facilitate early recognition and informed management of HRI, with the potential to improve patient outcomes.</p>