An emergency department response to severe acute respiratory syndrome: a prototype response to bioterrorism.

Study Objective: On March 13, 2003, Singapore physicians were alerted about an outbreak of atypical pneumonia that became known as severe acute respiratory syndrome (SARS). I describe the application of an emergency department (ED) disaster response plan to manage the SARS outbreak.

Methods: The ED implemented protection for staff, patients, and facility; infection control measures; and disaster-response workflow changes. The Ministry of Health, Singapore, centralized SARS cases in the hospital, and the ED became the national screening center. A screening questionnaire and a set of admission criteria were applied after assessment of clinical features and chest radiograph findings.

Results: For the duration of the outbreak that ended on May 31, 2003, the ED screened 11,461 persons for SARS, of whom 1,386 (12.9%) were admitted to rule out SARS and 235 (17%) were confirmed to have SARS. Among 10,075 persons discharged from the ED, there were 28 reattending patients who were admitted and diagnosed with SARS, giving an undertriage rate of 0.3% (95% confidence interval [CI] 0.1% to 0.4%). The sensitivity of an ED admission for SARS was 89.4% (95% CI 85.6% to 93.1%), and specificity was 89.7% (95% CI 89.2% to 90.3%). The positive predictive value was 17% (95% CI 15.7% to 18.4%), and the negative predictive value was 99.7% (95% CI 99.6% to 99.8%). No patient contracted SARS as a result of an ED visit. After full implementation of protective measures, 1 ED nurse with undiagnosed diabetes mellitus was treated for suspected SARS.

Conclusion: Although the SARS outbreak was not a bioterrorism event, the ED disaster response was applicable in the outbreak's management. The use of a screening questionnaire and admission criteria enabled the ED to screen, treat, and safely discharge the majority of the patients.