Abstract
Taiwan used quarantine as 1 of numerous interventions implemented to control the outbreak of severe acute respiratory syndrome in 2003. From March 18 to July 31, 2003, 147,526 persons were placed under quarantine. Quarantining only persons with known exposure to people infected with severe acute respiratory syndrome could have reduced the number of persons quarantined by approximately 64%. Focusing quarantine efforts on persons with known or suspected exposure can greatly decrease the number of persons placed under quarantine, without substantially compromising its yield and effectiveness.