Severe acute respiratory syndrome (SARS) is a serious form of pneumonia. It is caused by a virus that was first identified in 2003. Infection with the SARS virus causes acute respiratory distress (severe breathing difficulty) and sometimes death.
SARS is a dramatic example of how quickly world travel can spread a disease. It is also an example of how quickly a connected health system can respond to a new health threat.
World Health Organization (WHO) physician Dr. Carlo Urbani identified SARS as a new disease in 2003. He diagnosed it in a 48-year-old businessman who had traveled from the Guangdong province of China, through Hong Kong, to Hanoi, Vietnam. The businessman and the doctor who first diagnosed SARS both died from the illness.
In the meantime, SARS was spreading. Quickly it infected thousands of people around the world, including people in Asia, Australia, Europe, Africa, and North and South America. Schools closed throughout Hong Kong and Singapore. National economies were affected.
The WHO identified SARS as a global health threat, and issued a travel advisory. WHO updates closely tracked the spread of SARS. It wasn't clear whether SARS would become a global pandemic.
The fast global public health response helped to stem the spread of the virus. By June 2003, the number of new cases was down enough that on June 7, the WHO stopped its daily reports. But even though the number of new cases dwindled and travel advisories began to be lifted, every new case had the potential to spark another outbreak.
SARS appears to be here to stay. It has changed the way that the world responds to infectious diseases during a time of widespread international travel. The 2003 outbreak had an estimated 8,000 cases and 750 deaths. Deaths occurred mainly in older patients.