SARS (severe acute respiratory syndrome) is a severe pneumonia-like respiratory disease that first came to worldwide attention in southeast Asia in February 2003.
Pneumonia is a general term for an inflammation of the air sacs of the lungs caused by an infection or chemical. With pneumonia, the lungs fill with fluid, which interferes with their ability to transfer oxygen to the blood. SARS is known as an atypical pneumonia because it is not caused by the usual bacteria or viruses.
SARS causes high fever, severe breathing problems, and flu-like symptoms. Over 8,000 cases were reported worldwide during the 2003 outbreak. In Canada, about 10% of those infected with SARS died from the disease.
Putting things into perspective, the flu currently causes an estimated 250,000 to 500,000 deaths worldwide each year and as many as 2,000 to 8,000 Canadians die each year from flu and its complications. In contrast, during the SARS outbreak in 2003, there were 8,098 probable cases and 774 deaths from SARS worldwide. Since the outbreak, a few cases were reported in 2004 (from laboratory exposure), but no cases have been reported since.
A virus called coronavirus is the cause of SARS. There are many kinds of coronavirus, some of which cause the common cold. The SARS coronavirus (SARS-CoV) was a new variant that may have been transmitted to humans from animals.
How SARS spreads is not completely understood, but experts believe that the main way it spreads is through close contact with an infected person (someone who has cared for or lived with the person, or has had direct contact with their respiratory secretions and body fluids). The virus seems to be spread through aerosolized (exhaled) droplets and body secretions. You can come into contact with these materials when an infected person coughs or sneezes. You may also pick up the virus from surfaces such as doorknobs and elevator buttons.
Some experts believe that SARS may also be spread when fecal matter containing the virus is ingested (e.g., due to poor sewage treatment, contaminated food or water).
Most if not all cases of SARS in Canada during the 2003 outbreak occurred in:
- people who had recently travelled to Asia
- health care workers who had cared for SARS patients
- close family members of SARS patients
Symptoms and Complications
The main symptoms of SARS are:
- high fever (over 38°C or 100.4°F)
- dry cough, shortness of breath, and difficulty breathing
Usually, the fever appears first. Muscle aches, chills, headaches, sore throat, and diarrhea can often occur. About 1 or 2 days after these first symptoms, a dry cough and shortness of breath appear. Most people start to recover after 6 to 7 days.
However, some people go on to develop very severe breathing problems and may need the help of a machine (a ventilator) to help them breathe. The risk of dying from SARS is higher for this group. People over 50 and those with other medical conditions (e.g., heart problems, diabetes) are more likely to develop severe breathing problems.
Making the Diagnosis
Your doctor may suspect SARS if you experience symptoms of SARS during an outbreak. Your doctor will ask you about your symptoms, your travel history, and whether you may have come in contact with someone who has SARS.
If your doctor suspects you may have SARS, he or she may recommend that, instead of visiting the doctor's office, you go straight to a hospital. The hospital will take appropriate precautions to prevent the infection from spreading to others. During an outbreak, some hospitals set up clinics to specifically deal with SARS.
To diagnose SARS, a doctor will perform a physical examination and check for fever and swollen glands. He or she will also listen to your lungs with a stethoscope. Buildup of fluid in the lungs can be seen through a chest X-ray, CT scan, or with a magnetic resonance imaging (MRI) scanner. The doctor will send a sample of your sputum (phlegm) to a laboratory to confirm the diagnosis.
Treatment and Prevention
People with SARS must be treated in a hospital. Because the disease is severe, treatment needs to start based on symptoms, before the cause of the illness is confirmed. People who are suspected of having SARS are placed in isolation to protect other patients and health care workers. So far, no medication has been proven to cure SARS.
Treatment, for the most part, is supportive, and may include intravenous fluids (fluids injected into a vein) or a respirator to help with breathing. Although antibiotics will not help with SARS (as SARS is due to a virus), they may be used in cases where the person has developed a secondary bacterial infection. The benefit of antiviral medications or corticosteroids (e.g., prednisone*) has not been established.
There are currently no vaccines or medications that can protect you from SARS. To protect yourself from viral infections in general, practise good hand hygiene. Wash your hands frequently with soap and water and rub hands together briskly for at least 20 seconds; if your hands are not visibly soiled, alcohol-based hand rubs may be used as an alternative.
During an outbreak, health care workers should follow their institution's isolation policies when caring for SARS patients. If you are not a health care worker, avoid close personal contact with people who are known to have SARS or who are experiencing symptoms of SARS. Wash your hands often, especially before eating or touching your face.
*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For more information on brand names, speak with your doctor or pharmacist.