Chemical incident preparedness in Belgium has since long been open to improvement1. In 2020 the number of operational decontamination stations in front of emergency departments is still very low. Mobile decontamination stations are available but have limited capacity and long activation times. Time and time again, disaster retrospectives report varying numbers of victims who leave the disaster site outside of the regular medical disaster chain and/or EMS services, called wild evacuees. These wild evacuees also have the potential to bypass decontamination in the case of a potentially hazardous chemical incident2. Handling these contaminated victims is a severe potential hazard for all personnel involved in their care, either in prehospital setting or in the emergency department.
A systematic literature review was undertaken to identify contributing factors and the order magnitude of the wild evacuees in PubMed. 109 studies were identified. Only articles written in English and mentioning wild evacuees were included. Simulation exercises were excluded. Ten articles were included for further analysis. Review of the references identified an additional 3 articles eligible for inclusion.
Reported percentages of wild evacuation range from 0 to 89% in the Tokyo (Japan) Sarin terrorist attack3. A chlorine spill following a train derailment in Graniteville, South Carolina (USA) in 2005 reported 63% of victims being transported to the hospital outside EMS services. These transports included public transport, police cars, taxis or good Samaritans 4.
Possible contributing factors identified are the number of injured victims, the number of available ambulances, disaster type, disaster site characteristics, scene waiting time, proximity to hospitals, victim mobility, injury severity, time of day and personal hospital preference. Several studies also reported presentation of victims with mainly psychological injuries such as in Tokyo.
There are few retrospective analyses of reviews on the subject available in the literature. If there are mentions of wild evacuees, little is reported on their method of arrival or motivations. They frequently appear to present themselves to the closest hospitals, but sometimes also to their general practitioner or outpatient clinic.
Prehospital Emergency Physicians and department heads should be aware of the phenomenon of wild evacuees and the possibility of secondary contamination of personnel. In the case of a chemical mass casualty incident, the 112-center should quickly alert all hospitals of the possible arrival of contaminated victims. Scene incident managers should be aware of wild evacuees and take all available precautions to discourage this phenomenon.
Further research is needed, both for the prevalence of this phenomenon and the determining factors.
1. Mortelmans, Luc & Boxstael, Sam & Cauwer, H. & Sabbe, Marc. (2013). Preparedness of Belgian civil hospitals for chemical, biological, radiation, and nuclear incidents: Are we there yet?. European journal of emergency medicine : official journal of the European Society for Emergency Medicine. 21. 10.1097/MEJ.0000000000000072.
2. Heide, Erik. (2006). The Importance of Evidence-Based Disaster Planning. Annals of emergency medicine. 47. 34-49. 10.1016/j.annemergmed.2005.05.009.
3. Okumura, Tetsu & Suzuki, Kouichiro & Fukuda, Atsuhiro & Kohama, Akitsugu & Takasu, Nobuyuki & Ishimatsu, Shinichi & Hinohara, Shigeaki. (1998). The Tokyo Subway Sarin Attack: Disaster Management, Part 1: Community Emergency Response. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine. 5. 613-7. 10.1111/j.1553-2712.1998.tb02470.x.
4. Wenck, Mary & Van Sickle, David & Drociuk, Daniel & Belflower, Amy & Youngblood, Claire & Whisnant, M & Taylor, Richard & Rudnick, Veleta & Gibson, James. (2006). Rapid Assessment of Exposure to Chlorine Released from a Train Derailment and Resulting Health Impact. Public health reports (Washington, D.C. : 1974). 122. 784-92. 10.1177/003335490712200610.