Severe Acute Respiratory Syndrome (SARS)
Last Reviewed: October 2011
What is SARS?
Severe acute respiratory syndrome (SARS) is a viral respiratory illness that was first reported in Asia in February 2003. Over the next few months, the illness spread to more than two dozen countries in North America, South America, Europe and Asia. By late July 2003, no new cases were being reported and the outbreak was considered contained. During this outbreak, 8,098 people worldwide became sick with SARS, resulting in 774 deaths. The most recent cases of SARS were reported in China in April 2004 in an outbreak resulting from exposures to the virus that occurred in a laboratory.
What are the symptoms and signs of SARS?
The illness usually begins with a high fever (temperature greater than 100.4 degrees F). The fever is sometimes associated with chills or other symptoms, including a headache, a general feeling of discomfort and body aches. Some people also experience mild respiratory symptoms at the outset. Approximately 10-20 percent of patients have diarrhea. After two to seven days, SARS patients may develop a dry cough with most developing pneumonia.
What is the cause of SARS?
SARS is caused by a coronavirus called SARS-associated coronavirus. Coronaviruses are a common cause of mild to moderate upper respiratory illness in humans. There is not enough information about the virus to determine the full range of illness that it might cause. Coronaviruses have occasionally been linked to pneumonia in humans, especially people with weakened immune systems. The viruses also can cause severe disease in animals, including cats, dogs, pigs, mice and birds.
How is SARS Spread?
SARS is mainly spread by close person-to-person contact. The virus that causes SARS is thought to be transmitted most readily by being within 3 feet of respiratory droplets produced when an infected person sneezes and/or by touching a surface or object contaminated with infectious droplets. Close contact is defined as having cared for or lived with a person known to have SARS or having direct contact with secretions and/or body fluids of a patient known to have SARS. Examples include kissing or embracing, sharing eating or drinking utensils, close conversation (within three feet) or physical contact. Close contact does not include walking near a person or sitting across a waiting room or office for a brief time.
Who is at risk for getting SARS?
Most exposures to SARS occur in healthcare facilities and households. Community transmission outside of these settings has been reported, but these occurred rarely. Persons at risk in healthcare facilities include healthcare workers, patients and visitors. In households, the greatest risk is to family members of SARS patients. Transmission could occur in a laboratory if proper safety procedures are not strictly followed.
In addition, it is possible that SARS virus might be spread more broadly through the air or by other ways that are not yet known.
If I were exposed to SARS, how long would it take for me to become sick?
The incubation period (the time between exposure to the SARS virus and onset of symptoms) is typically two to seven days, although in some cases it may be as long as 10 days.
How long is a person with SARS infectious to others?
Information suggests that people with SARS are most likely to be infectious only when they have symptoms such as fever or cough. However, as a precaution against spreading the disease, CDC recommends that people with SARS limit their interactions outside the home (stay home from work and school) until 10 days after their symptoms have gone away.
Do some people who recover from SARS become sick again or relapse?
CDC and other scientists are trying to gain a full understanding of what factors might influence illness progression and recovery. Such factors could be related to the virus itself, how the body's immune system reacts to the virus or how infection with the virus is treated.
How widespread was the SARS outbreak in the United States?
Through July 2003, a total of 192 SARS cases had been reported in the United States, including 159 suspect and 33 probable cases; of the 33 probable cases only 8 had laboratory evidence of the SARS virus. No SARS-related deaths occurred in the U.S. SARS cases reported in the U.S. occurred primarily among people who traveled to SARS-affected areas; a small number of people became ill after being in close contact with (having cared for or lived with) a SARS patient while in the U.S.
What was done to contain the SARS outbreak in the U.S.?
To minimize the risk for SARS among U.S. residents, the public health system took careful and thorough precautions to prevent the spread of SARS. People who were suspected of having SARS were isolated from others and received care. People arriving from affected parts of the world (who might have been exposed to SARS) received information about SARS and instructions on what they should do if they became ill. SARS patients and their contacts were monitored to help prevent spread of the disease.
What did CDC do to combat the SARS outbreak?
CDC worked closely with the World Health Organization (WHO) and other partners in a global effort to address the SARS outbreak. For its part, CDC took the following actions:
- Activated its Emergency Operations Center to provide round-the-clock coordination and response.
- Committed more than 900 medical experts and support staff to work on SARS response.
- Deployed medical officers, epidemiologists and other specialists to assist with on-site investigations around the world
- Provided assistance to state and local health departments to investigate possible cases of SARS in the United States.
- Conducted extensive laboratory testing of clinical specimens from SARS patients to identify the cause of the disease.
- Initiated a system for distributing health alert notices to travelers who have been exposed to cases of SARS.
In addition, CDC is continuing to work with federal, state and local health departments and other professional organizations to plan for a rapid recognition and response should SARS re-emerge.
What is New York State doing to prepare its citizens for a possible reappearance of SARS?
New York State is preparing for the possible reappearance of SARS by:
- Educating healthcare workers about SARS diagnosis and reporting,
- Developing SARS surveillance systems to determine if and where SARS has re-emerged,
- Developing guidelines for preventing transmission in different settings, and
- Improving laboratory tests for SARS.
If there is another outbreak of SARS, how can I protect myself and my family?
If SARS were to reemerge, there are some common sense precautions that you can take that apply to many infectious diseases. The most important is frequent hand washing with soap and water or use of alcohol-based hand rubs. You should avoid touching your eyes, nose and mouth with unclean hands and encourage people around you to cover their nose and mouth with a tissue when coughing or sneezing.
Is it safe to travel to other countries outside of the U.S.?
At this time, there is no evidence of ongoing transmission of SARS anywhere in the world. In the absence of SARS transmission, there is no need for concern about travel or other activities.