SARS

Related Terms

Antivirals, coronavirus, corticosteroids, face mask, hypoxia, infection, interferons, lung infection, respiratory failure, respiratory infection, SARS outbreak, severe acute respiratory syndrome, supplemental oxygen, viral infection, virus.

Background

Severe acute respiratory syndrome, commonly called SARS, is a contagious respiratory infection that sometimes causes death. SARS is caused by a type of virus called coronavirus. Researchers believe that one or more animal viruses evolved over time into this new type of coronavirus.
The first case of SARS occurred in China in 2002. In just six weeks, the virus spread to several areas around the globe. From November 2002 to July 2003, the virus was reported in more than 29 countries in Asia, Europe, North America, and South America. During this time, more than 8,098 patients became infected with SARS, and more than 900 died, according to the World Health Organization (WHO). Eight cases of SARS have been reported in the United States. The SARS outbreak was over by the spring of 2004.
Since the outbreak, only a few cases in humans have been reported each year. This is because health officials have contained the virus, and if it is suspected that an individual is infected, precautionary measures are taken to prevent SARS from spreading. In order for anther outbreak to occur, the virus would have to be transmitted from a laboratory accident, animal source, or humans who were not diagnosed, isolated, and treated quickly.
In addition, scientists believe that some of the cases that were originally diagnosed as SARS may have actually been a more deadly disease called bird flu (avian influenza).
The prognosis for SARS patients varies. However, the death rate is generally considered much higher than the common influenza (flu). About 14-15% of patients who develop SARS die. In patients older than 65 years of age, the death rate is estimated to be higher than 50%.
Currently, treatment for SARS is limited. Patients typically receive a combination of antiviral medications and corticosteroid medications, although the effectiveness of this therapy has not been proven. Additional care, such as oxygen, may also be needed.

Signs and symptoms

It is believed that patients are only contagious when symptoms are present. Patients are most contagious the second week after symptoms develop. The U.S. Centers for Disease Control and Prevention (CDC) recommends that individuals avoid public areas for at least 10 days after symptoms go away. Detailed information on how to prevent the transmission of severe acute respiratory syndrome (SARS) can be found in the prevention section.
Between two and 10 days after exposure to the SARS virus, patients typically develop a temperature of 100.4 degrees Fahrenheit or higher. Symptoms typically include soreness, chills, muscle soreness, headache, and general feeling of discomfort.
In some patients, SARS is progressive and worsens over time. SARS is fatal in some patients. Most deaths are the result of lung, heart, and/or liver failure. An estimated 10-20% of patients develop severe pneumonia and breathing problems that lead to an insufficient amount of oxygen in the blood. Low levels of oxygen in the blood may lead to respiratory failure or death.

Diagnosis

Several tests are available to diagnose severe acute respiratory syndrome (SARS). If SARS is suspected, one or more of the below tests may be performed. Doctors are required to report cases of SARS to the World Health Organization (WHO).
Blood test: A blood test may be performed to determine if the patient has antibodies to the SARS virus. Antibodies are substances that the body produces to fight against specific bacteria, viruses, and other microbes. If the antibodies are present, SARS is diagnosed.
DNA test: During a DNA test, a sample of blood, stool, or mucus from the nose is taken from the patient. The sample is then analyzed for the presence of the coronavirus' DNA. If the viral DNA is present, a positive diagnosis is made.
Viral culture: During a viral culture test, a small sample of tissue, blood, or mucus from the nose is taken from the patient. The sample is placed on a petri dish and allowed to grow in a laboratory. If the coronavirus grows on the petri dish, a positive diagnosis is made.

Treatment

General: Treatment is limited for patients with severe acute respiratory syndrome (SARS). A combination of antiviral drugs that are normally used to treat HIV/AIDS have been shown to prevent serious complications and deaths related to SARS. However, further research is needed to verify that this is a safe and effective treatment. Patients diagnosed with SARS should take medications exactly as prescribed and stay in close contact with their doctors.
Eat healthfully and rest: Eating a well-balanced diet and getting about eight hours of sleep a night may help boost the immune system. Having a strong immune system helps the body fight against infections, including SARS.
Antibiotics: Patients typically receive broad spectrum antibiotics while they wait for their laboratory results. If the patient has SARS, antibiotics will be stopped. This is because antibiotics are used to treat bacterial infections and are ineffective at treating viral infections.
Antivirals: Patients typically receive a combination of antiviral medications, usually ribavirin and lopinavir/ritonavir (Kaletra?). Although laboratory studies suggest that these medications may help treat SARS, their efficacy remains unclear.
Patients should take medications exactly as prescribed. Even if symptoms appear to go away, patients should take all of their medication because the virus may still be in the body. Stopping medication early may allow the infection to return. Also, stopping medication early may lead to drug resistance. The few remaining viral particles in the body that survive most of the antiviral therapy are the most difficult to kill. If the virus becomes resistant to treatment, the medications will no longer be effective if taken in the future.
Antivirals should be used cautiously in patients with liver disorders or dysfunction. Side effects may include nausea, vomiting, diarrhea, stomach pain, bloating, numbness or tingling (especially around the mouth), mood changes, headache, and changes in the shape or location of body fat.
Corticosteroids: Patients may also receive medications called corticosteroids. These medications help reduce severe inflammation. Because these medications are normally given to patients with lung diseases (such as emphysema) to prevent and reduce airway swelling and decrease the amount of mucus in the lungs, they are also given to SARS patients. However, the role of steroids in the treatment of SARS is not fully understood.
Corticosteroids are usually prescribed for a certain amount of time, and then the patient is gradually tapered off the medication. Patients should not stop taking corticosteroids suddenly or change their dosages without first consulting their healthcare providers. Corticosteroids may cause severe swelling (edema) that can lead to dangerously high blood pressure.
Interferons: Interferons have also been suggested as a possible treatment for SARS. Several types of interferons, including interferon beta-1b (Betaseron?), interferon gamma-1b (Actimmune?), interferon alpha-2a (Roferon-A?), and alfa-2b (Intron-A?), have been studied. Interferon medication is a man-made version of a protein that is involved in the immune system. The body produces interferons to help fight against disease and infection. These proteins stimulate immune cells to destroy body cells that have become infected with viruses. Early research suggests that this therapy may help treat patients with SARS. However, further research is needed to determine the effectiveness of this therapy.
Side effects may include depression, flu-like symptoms, tissue damage, fatigue, nausea, diarrhea, vomiting, joint aches, abdominal pain, back pain, and dizziness. Less common side effects may include loss of appetite, stuffy nose, increased heart rate, confusion, low white blood cell count, low red blood cell count, low platelet count, increase in liver enzymes, increase in triglycerides, mild hair loss, temporary skin rash, swelling (edema), difficulty breathing, and cough.
Supplemental oxygen: Patients with progressive SARS who have low oxygen levels in the blood may receive supplemental oxygen. This may be delivered in the form of a nasal cannula or face mask. If the patient experiences respiratory failure, he/she will need to be hooked up to a mechanical ventilator. This machine pumps air in and out of the lungs for the patient.

Integrative therapies

Unclear or conflicting scientific evidence:
Traditional Chinese medicine (TCM): Chinese medicine is a broad term that refers to many different treatments and traditions of healing. They share a common heritage of technique or theory rooted in ancient Chinese philosophy (Taoism) that dates back more than 5,000 years. Early evidence suggests that TCM may help stimulate the immune system and decrease depression associated with SARS. However, a firm conclusion cannot be made at this time because some studies have produced conflicting results.
TCM should be used cautiously. Side effects, as well as interactions with herbs, drugs, supplements, and foods, are possible.
Traditional or theoretical uses, which lack sufficient evidence:
Lemongrass: Lemongrass oil is an essential oil used in deodorants, herbal teas, skin care products, fragrances, and insect repellents. It is also commonly used during aromatherapy. Although lemongrass has been suggested as a possible treatment for severe acute respiratory syndrome (SARS), scientific studies are lacking in this area.
Avoid if allergic to lemongrass, its constituents, or any members of the Poaceae family. Use cautiously if taking diabetic or cardiac medications or medications that are broken down by the liver. Use cautiously with liver conditions. Avoid if pregnant or breastfeeding.
Licorice: Licorice is harvested from the root and dried rhizomes of the low-growing shrub Glycyrrhiza glabra. It has been suggested, but not proven, that licorice may help treat SARS. Until studies are performed to evaluate the safety and efficacy of this treatment, a firm conclusion cannot be made.
Avoid if allergic to licorice, any component of licorice, or any member of the Fabaceae (Leguminosae) plant family. Use cautiously with congestive heart failure, coronary heart disease, kidney disease, liver disease, fluid retention, high blood pressure, hormonal abnormalities, or underlying electrolyte disturbances. Avoid if taking diuretics. Licorice may cause abnormally low testosterone levels in men or high prolactin or estrogen levels in women. This may make it difficult to become pregnant and may cause menstrual abnormalities.
Rhubarb: Rhubarb is an herb that is commonly used in traditional Chinese medicine (TCM). Rhubarb has been suggested as a possible treatment for SARS. However, studies have not been performed to determine if this treatment is safe and effective.
Avoid if allergic to rhubarb, its constituents, or related plants from the Polygonaceae family. Avoid using rhubarb for more than two weeks. Avoid with atony, colitis, Crohn's disease, dehydration with electrolyte depletion, diarrhea, hemorrhoids, insufficient liver function, intestinal obstruction, ileus, irritable bowel syndrome (IBS), pre-eclampsia, kidney disorders, ulcerative colitis, urinary problems, or during menstruation. Avoid handling rhubarb leaves, as they may cause contact dermatitis. Avoid rhubarb in children younger than 12 years old due to water depletion. Use cautiously with bleeding disorders, cardiac conditions, constipation, history of kidney stones, or thin or brittle bones. Use cautiously if taking anticoagulants (blood thinners), anti-psychotic drugs, or oral drugs, herbs, or supplements (including calcium, iron, and zinc). Avoid if pregnant or breastfeeding.

Prevention

General: Researchers are currently working to develop a vaccine for SARS. In the meantime, there are many ways to reduce the risk of becoming infected with SARS.
Precautions during travel: Individuals are encouraged to learn as much about SARS as possible before planning a trip to areas known to have had SARS outbreaks. The U.S. Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have updated information on their Web sites. In addition, patients are encouraged to talk to their healthcare providers before traveling to such areas.
It has been suggested that infections may spread on airplanes through the vents above the seats. As a precautionary measure, individuals may want to consider turning these vents off.
Individuals are also encouraged to check their travel insurance. Individuals can purchase coverage for medical evacuation if they are traveling to countries that have had outbreaks of SARS or other infectious diseases.
When individuals are planning their trips, they should look up recommended doctors and hospitals near their destinations. This ensures that individuals will know where to go in case of a medical emergency.
Individuals should not visit live food markets in China. Civet cats sold in these markets are known to carry viruses similar to the SARS virus.
Frequently washing the hands with warm water and soap and using hand sanitizers may help reduce the risk of acquiring contagious infections. Individuals can also wear face masks if they are travelling to areas where infectious diseases are common.
Preventing infection when taking care of SARS patients: Individuals who have been exposed to or are caring for someone who is infected with the SARS virus should take precautions to prevent acquiring infections. The precautions listed below should be followed for at least 10 days after the infected person's signs and symptoms have gone away.
Individuals should wash the hands frequently with soap and hot water.
Individuals who are exposed to the SARS virus should not touch their face, especially their nose, mouth, or eyes.
Individuals should wear surgical masks when they are in the same room as a person infected with SARS. Wearing glasses may also help protect against acquiring the infection.
Disposable gloves (such as rubber gloves) should be worn when touching an infected person's body fluids or feces. The gloves should be thrown out after a single use, and the hands should be thoroughly washed with soap and hot water.
Any items that an infected person comes into contact with, such as bed linens, towels, clothing, and food utensils, should be washed with soap and hot water. Any surfaces, such as the kitchen counter, nightstand, or bathroom sink, should be cleaned with a disinfectant if they become contaminated with body fluids of the infected person. Individuals should wear disposable gloves while washing or cleaning contaminated objects.
Preventing transmission if infected: Individuals who are already infected with the SARS virus should take steps to reduce the risk of spreading the infection on to others. The precautions listed below should be followed for at least 10 days after the signs and symptoms of the infection have gone away.
Do not go to school, work, or other public places.
Individuals should cover their mouths and noses with tissues when they sneeze or cough. Individuals should wear surgical masks when in close contact with others.
Frequently wash the hands with soap and hot water.
Do not share bed linens, towels, clothing, silverware, or other items with other people until they have been properly cleaned with soap and hot water.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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Goh KT, Cutter J, Heng BH, et al. Epidemiology and control of SARS in Singapore. Ann Acad Med Singapore. 2006 May;35(5):301-16.
Liang WN, Huang Y, Zhou WX, et al. Epidemiological characteristics of an outbreak of severe acute respiratory syndrome in Dongcheng District of Beijing from March to May 2003. Biomed Environ Sci. 2003 Dec;16(4):305-13.
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Causes

General: Severe acute respiratory syndrome (SARS) is caused by a type of virus called coronavirus. Researchers believe that one or more animal viruses evolved over time into this new type of coronavirus. For instance, one theory is that the coronavirus originated in civet cats, which are weasel-like animals found in Asia. These animals were sold in Guangdong, a southern region of China, as a delicacy. Some scientists believe that close contact with civet cats or their feces or saliva may have transmitted a mutated form of the virus to humans.
The coronavirus is in the same family as the common cold. However, if an individual gets the common cold, it will not develop into SARS.
Transmission: The SARS virus is highly contagious. It can spread from person to person through airborne mucus droplets from an infected person. Mucus droplets may enter the air when an infected person coughs, sneezes, laughs, talks, etc. An individual can become infected with SARS if he/she inhales these mucus droplets or particles.
The virus may also spread through contaminated objects, including telephones, doorknobs, stairway railings, and elevator buttons. If a person touches a contaminated object and then touches his/her face, the virus may enter the body and cause an infection.