Investigation of a Mass Casualty Bus Accident Involving a Collision with a Road Median Tree in Pradang Subdistrict, Wang Chao District, Tak Province, on February 5, 2025

Abstract

On February 5, 2025, the Situation Awareness Team (SAT) of the Office of Disease Prevention and Control Region 2, Phitsanulok, was notified by the Tak Provincial Public Health Office of a mass casualty incident involving the bus (Bangkok–Chiang Mai route) that crashed into a roadside tree in Wang Chao District, Tak Province. The Joint Investigation Team (JIT) conducted a field investigation on February 6–7, 2025, in collaboration with the Tak Road Traffic Accident Analysis Committee. The objectives were to determine contributing factors of the crash, to review preventive measures, and to propose strategies to reduce injuries and fatalities in similar events. Contributing factors were analyzed with Haddon’s Matrix Model. Using the Haddon’s Matrix Model, the team assessed medical outcomes, environmental conditions, and contributing factors. The incident involved 35 passengers, resulting in 2 fatalities and 33 injuries, predominantly foreign nationals aged 7–70 years. Injuries included trauma to limbs, hips, chest, and head, while fatalities were due to severe head injuries. Key contributing factors were driver fatigue, insufficient rest, nighttime driving, lack of seat belt use, long straight road sections with large trees in the median, absence of guardrails and rumble strips, and seat detachment during impact. The Department of Highways should consider installing guardrails and rumble strips in high-risk areas to prevent similar accidents. Strengthened collaboration among transport operators, drivers, and authorities is essential to reduce preventable road traffic injuries and fatalities.