Severe acute respiratory syndrome (SARS)

DEFINITION

Severe acute respiratory syndrome (SARS) is a contagious and sometimes fatal respiratory illness. SARS first appeared in China in November 2002. Within a few months, SARS spread worldwide, carried by unsuspecting travelers.

SARS showed how quickly infection can spread in a highly mobile and interconnected world. On the other hand, concerted international cooperation allowed health experts to quickly contain the spread of the disease. There has been no known transmission of SARS anywhere in the world since 2004.

CAUSES

SARS is caused by a strain of coronavirus, the same family of viruses that causes the common cold. Until now, these viruses have never been particularly dangerous in humans, although they can cause severe disease in animals. For that reason, scientists originally thought that the SARS virus might have crossed from animals to humans. It now seems likely that it evolved from one or more animal viruses into a new strain.

How SARS spreads

Most respiratory illnesses, including SARS, spread through droplets that enter the air when someone with the disease coughs, sneezes or talks. Most experts think SARS spreads mainly through face-to-face contact, but the virus also may be spread on contaminated objects — such as doorknobs, telephones and elevator buttons.

SYMPTOMS

SARS typically begins with flu-like signs and symptoms — fever, chills, muscle aches and occasionally diarrhea. After about a week, signs and symptoms include:

• Fever of 100.5 F (38 C) or higher
• Dry cough
• Shortness of breath

When to see a doctor

If you think you’ve been exposed to or have SARS, see your doctor right away. SARS is a serious illness that can lead to death.