Objective The purpose of this study was to investigate barriers to surge capacity of an overcrowded emergency department (ED) for a foodborne disease outbreak (FBDO) and to identify solutions to the problems.

Design The emergency response of an overcrowded ED to a serious FBDO with histamine fish poisoning was reviewed.

Setting The ED of a tertiary academic medical centre (study hospital) with 1600 acute beds in southern Taiwan.

Results Among the 346 patients in the outbreak, 333 (96.2%) were transferred to the study hospital without prehospital management within about 2 h. The most common symptoms were dizziness (58.9%), nausea and vomiting (36.3%). 181 patients (54.4%) received intravenous fluid infusion and blood tests were ordered for 82 (24.6%). All patients were discharged except one who required admission. The prominent problems with surge capacity of the study hospital were shortage of spare space in the ED, lack of biological incident response plan, poor command system, inadequate knowledge and experience of medical personnel to manage the FBDO.

Conclusions Patients with FBDO could arrive at the hospital shortly after exposure without field triage and management. The incident command system and emergency operation plan of the study hospital did not address the clinical characteristics of the FBDO and the problem of ED overcrowding. Further planning and training of foodborne disease and surge capacity would be beneficial for hospital preparedness for an FBDO.