· SARS (Severe Acute Respiratory Syndrome) is a contagious and sometimes fatal viral respiratory illness.
· After a first outbreak in China, it spread to many other countries in early 2003.
· SARS has now been completely contained, although another outbreak may occur in the future.
· The virus that causes SARS is called SARS-associated coronavirus (SARS-CoV).
· The primary mode of transmission appears to be close person-to-person contact.
· Symptoms are similar to those of other respiratory illnesses like flu and pneumonia.
· In the case of a future outbreak, if you have close contact with an infected person, you should monitor your health for at least 10 days and consult your doctor if you develop symptoms.
· There is not yet an effective treatment available for SARS.
What is SARS?
SARS (Severe Acute Respiratory Syndrome) is a contagious and sometimes fatal viral respiratory illness. The first case of SARS was reported in late 2002 in China, and it was identified as a new disease in 2003. The disease was spread by travellers to countries in Europe, Asia and North and South America, causing over 8 000 infections and nearly 800 deaths before it was brought under control in July 2003.
The unexpected emergence and spread of SARS demonstrated how the high mobililty of people in the 21st century can contribute to infections rapidly becoming global problems.
SARS has now been completely contained. The most recent human infections, in Beijing in 2004, were of workers at a laboratory handling the virus. However, SARS has not been definitively eradicated: it may still exist in animal populations, in which case it might enter the human population again in the future.
What causes SARS?
SARS is caused by a previously unrecognized type of coronavirus, a family of viruses that usually only causes mild upper respiratory tract infections in humans - but serious illnesses in animals. The virus that causes SARS is called SARS-associated coronavirus (SARS-CoV); it is thought to have evolved from one of the animal viruses into a new strain.
Other infectious agents may also play a role in some cases of SARS.
The primary mode of transmission for SARS appears to be close person-to-person contact. When an infected person coughs or sneezes, droplets are propelled into the air and can be deposited on mucous membranes of the mouth, nose or eyes of people close by. It seems that the virus can also spread if you touch an object contaminated with infectious droplets and then touch your mouth, nose or eyes.
Some people seem to have acquired the infection on airplanes, suggesting that the virus might also spread more widely through the air (airborne particles, smaller than droplets, travel further and persist for longer in the air).
The virus may also be transmitted in contaminated sewage, or in other ways not yet understood.
An infected person is probably most contagious while they have active symptoms (i.e. during the second week of illness), but it is uncertain whether SARS can also be spread to others before symptoms begin or after they've disappeared. Therefore, it is recommended that people who have recovered from SARS do not go out in public until 10 days after their symptoms have resolved.
Symptoms of SARS
The symptoms of SARS are similar to those of other respiratory illnesses like flu and pneumonia.
Symptoms usually appear two to seven days after infection, although sometimes the incubation period may be as long as 10 days. SARS usually begins with a high fever, and mild respiratory symptoms in some cases (shortness of breath or breathing difficulties). Chills, headache, muscle aches, malaise (generally feeling unwell) and a dry cough are also common. Some people develop diarrhoea.
Most people with SARS develop pneumonia. There is a danger of hypoxia, a condition in which the oxygen levels in the blood fall to dangerously low levels. Patients may require mechanical ventilation. SARS is fatal in some cases, often as a result of respiratory failure. Other potential complications include heart and liver failure.
It is not clear why the disease proves deadly in some people and not in others. Although many of the deaths in the last outbreak were among older adults with existing health problems, there have also been fatal cases of SARS in young, healthy people.
During a possible future SARS outbreak, you are at greatest risk if you have had close contact with an infected person, such as a family member. ‘Close contact’ involves caring for or living with an infected person or having direct contact with their respiratory secretions or body fluids. Examples of close contact: kissing, sharing eating utensils or personal items, talking to the person face-to-face, or touching him or her directly.
Scientists have identified a genetic variation that may make a person’s immune system less able to fight the SARS virus. The genetic variation is common among people of Southeastern Asian descent, which may be one of the reasons that most SARS cases have occurred in this part of the world.
When to see a doctor
If you have close contact with an infected person, you should monitor your health for at least 10 days afterwards, and consult your doctor immediately if you develop any symptoms during that time.
There are now laboratory tests available that can help to determine if you are infected with the virus. If you are ever concerned that you may have been exposed to SARS, ask your doctor if such tests would be appropriate in your case.
There is not yet an effective treatment available for SARS. People with the disease are treated as they would be for any serious community-acquired atypical pneumonia. Researchers are testing various antiviral drugs on the SARS virus in the quest to find an effective treatment.
In the event of another SARS outbreak, certain guidelines should be followed to help prevent transmission (these precautions apply to many infectious diseases):
· Wash your hands frequently and well with soap and water (preferably hot), or alternatively use an alcohol-based hand rub.
· Don’t touch your face with unwashed hands; rather use disposable tissues.
· Cover your nose and mouth with a tissue when coughing or sneezing, and encourage those around you to do likewise.
In addition, If you're caring for someone at home with SARS:
· Wear disposable gloves if you’re going to have contact with the person's body fluids. Dispose of the gloves immediately after use and wash your hands well.
· Wear a surgical mask while in the same room as the sick person. Wearing glasses/goggles may also provide some protection.
· Wash the sick person’s eating utensils, towels, bedding and clothing with hot water and detergent. No-one else should use these items until they're clean.
· Use disinfectant to clean surfaces that may have come into contact with infected body fluids. Wear gloves during cleaning and dispose of them afterwards.
· Continue to follow the above precautions for at least 10 days after the person is symptom-free.
In addition to the general precautions above, if you are infected with SARS:
· Wear a surgical mask when in the company of other people.
· Don't allow anyone to use your eating utensils, towels or bedding unless these items have been properly cleaned.
· Don’t go out in public for at least 10 days after you are completely symptom-free, and after consulting your doctor.
Adapted for Health24 by Olivia Rose-Innes from CDC material, August 2011
Centre for Disease Control SARS Factsheet