Severe acute respiratory syndrome (SARS) is an infectious disease first identified in humans in early 2003.
SARS is caused by a newly described coronavirus, called SARS-associated coronavirus (SARS-CoV). Previously identified human coronaviruses (named for their spiky, crown-like appearance) were known to cause only mild respiratory infections.
SARS typically begins with flu-like symptoms, including high fever that may be accompanied by headache and muscle aches, cough, and shortness of breath. Up to 20 percent of infected people may develop diarrhea. Most people with SARS subsequently develop pneumonia.
In the 2003 outbreak, there were more than 8,000 probable cases of SARS and 774 deaths (approximately 9 percent mortality), according to the World Health Organization. Eight confirmed cases were identified in the United States, with no deaths. Of the 774 deaths attributed to SARS, more than 50 percent occurred in people 65 years of age or older. Susceptibility decreased significantly with age, with children the least likely to acquire the disease.
The virus spreads primarily by close human contact. SARS-CoV-containing droplets can be released into the air when an infected person coughs or sneezes. Some specific medical procedures performed on SARS patients also can release virus-containing droplets into the air. Touching a SARS-CoV-infected surface and subsequently touching the eyes, nose, or mouth also may lead to infection.
Intensive and supportive medical care is the primary therapy because no specific treatment has yet been shown to consistently improve the outcome of the ill person.
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Last Updated March 04, 2009
Last Reviewed March 04, 2009