ABSTRACT
INTRODUCTION In February 2003, physicians at a hospital in Hanoi, Vietnam, sought advice from the local WHO office regarding a patient who had presented with an unusual influenza-like illness (1). Dr Carlo Urbani, an infectious disease specialist who responded to the request soon notified the WHO of an outbreak of severe respiratory disease. In the ensuing weeks, it became clear that similar outbreaks were occurring in several locations including Hong Kong, southern China, and Canada, and that patients in diverse locations had stayed at the same hotel in Hong Kong. The syndrome was called severe acute respiratory syndrome (SARS) and was characterized by fever, chills or rigors, headache, and nonspecific symptoms such as malaise andmyalgias, followed by cough and dyspnea (2,3). Respiratory tract disease progressed to acute respiratory distress syndrome requiring intensive care and mechanical ventilation in more than 20% of patients. Prolonged hospitalizations associated with complications were reported, and advanced age was an independent correlate of adverse clinical outcome and increased mortality. The outbreak was notable for spread in health care settings, affecting large numbers of health care workers, and for a rapid dissemination to distant parts of the world by infected travelers.
