Table 1.

Factors Leading to the Global Alert Issued by WHO on March 15, 20032

1.The causative agent and the potential for spread were still unknown. 2.The outbreaks appeared to pose a great risk to health care workers, family members, and other close contacts of patients. 3.None of the different antibiotics and antivirals that had been tried empirically seemed to have an effect. 4.Although the numbers still were relatively small, the clinical course had progressed rapidly to respiratory failure, requiring intensive care, and many previously healthy patients had died. 5.The disease had spread from its initial focus in Asia to North America and Europe.