Mass Gathering Emergency Medicine: A Review of the Taiwan Experience of Long-distance Swimming Across Sun-Moon Lake

Abstract

Once a year during the festival of Sun-Moon Lake in Nan-Tou County, Taiwan, a long-distance swimming mass gathering (LDSMG) event takes place. This event, in which participants swim an estimated 30 km, is very popular; the total number of spectators and participants at the 2002 festival was 15,189. This study, the first pertaining to the LDSMG, aimed to review the effect of the environmental factors at this particular mass gathering event, with mass being defined here as more than 1,000 people, upon the event's patient presentation rate (PPR). This was done to provide improved medical services at this event in future years The study also aimed to collect patient data from the two medical stations (one upstream and one downstream) and analyze the differences between them. In 2002, the number of patients requiring first aid treatment was determined from data gathered on-site. A total of 63 presented at on-site medical stations (PPR, 4.15 per 1,000 attendees), where 14 patients presented to a downstream medical station and 49 to an upstream medical station. The mean age of the patients was 35.46 ± 15.14 years; ages ranged from 1 to 65 years. Forty-nine of the patients (78%) were male. Fifty-nine patients were treated with medication (3.88 per 1,000 attendees), and two were taken to hospital (0.13 per 1,000 attendees). Injuries sustained included trauma (71%), such as impact, fall, sprain, stabbed laceration and burn, hypothermia (5%), and foreign bodies (3%). The PPR at the LDSMG was related to factors including the presence or absence of seating, whether the event was outdoors or indoors, mobility of the crowd, whether the activity was contained within a boundary, attendance figures, and humidity level. The weather, particularly the relative humidity (81%), was also positively correlated with an increase in the number of presentations at the medical stations.