Heat-related illnesses in the Republic of Korea Armed Forces: epidemiology, comparative analysis, and preventive strategies.

Heat-related illnesses (HRIs) represent an increasingly critical threat to the health and operational readiness of the Republic of Korea (ROK) Armed Forces. Rising global temperatures, combined with Korea's humid summers and intensive military training, have increased both the incidence and severity of HRIs among soldiers. This paper provides a comprehensive review of HRIs in the ROK military, beginning with an overview of their pathophysiology and classification, ranging from heat cramps to exertional heat stroke-the most severe and life-threatening form. We then examine recent epidemiological trends, which reveal over 1,200 documented cases between 2018 and 2023, with new recruits disproportionately affected. A comparative analysis across service branches indicates that Army personnel, who engage in high-intensity outdoor training, bear the greatest burden, while Navy and Air Force members face distinct occupational exposures in engine rooms and on airfields, respectively. The risk in the ROK military is striking in international comparison: odds ratios suggest that soldiers face more than 27 times the risk of HRIs compared with the civilian population, exceeding reported burdens in allied militaries such as the United States and Japan. Lessons from other nations, particularly the use of real-time surveillance, wearable technologies, and structured acclimatization programs, offer valuable models for ROK. Preventive strategies must therefore extend beyond medical management to include leadership accountability, environmental engineering, digital monitoring, and a cultural shift that promotes reporting. In an era of accelerating climate change, HRIs must be reframed not only as medical conditions but also as preventable threats to combat readiness, soldier welfare, and national security.