All you need to know about SARS
<a href=iol.co.za>IOL March 31 2003 at 02:13PM
Hong Kong - A highly contagious respiratory virus spreading across the world has killed 59 people and infected more than 1 600 others, mainly in Asia.
Here are facts about severe acute respiratory syndrome (SARS), an atypical type of pneumonia:
What is it?
Scientists say SARS is caused by a new virus from the family of coronaviruses, which also causes the common cold.
The United States Centre for Disease Control and Prevention has confirmed that the virus is the primary causative agent, but experts say much laboratory work still needs to be done to pinpoint its exact characteristics. Development of a vaccine will take years.
The World Health Organisation says the disease originated in China's southern province of Guangdong, before spreading to Hong Kong, where it was then carried to Vietnam, Singapore and Canada. Other cases later surfaced in the United States, France, Britain, Taiwan and Germany.
Hong Kong and WHO scientists say the strain likely originated from animals.
Health experts in Hong Kong have ruled out any association with influenza A and B viruses, and also the H5N1 bird-flu virus which jumped the species barrier and killed six people in the territory in 1997, and one man in February.
SARS is a type of atypical pneumonia, which is usually caused by viruses, such as influenza viruses, adeno-virus and other respiratory viruses, according to Hong Kong health officials.
Atypical pneumonia can also be caused by organisms such as legionella, although that is rare in Hong Kong.
WHO officials say there is no indication that SARS is linked to bioterrorism.
What are the symptoms?
The WHO says the main symptoms of SARS are high fever (over 38°C), a dry cough, shortness of breath or breathing difficulties. Changes in chest X-rays, which are indicative of pneumonia, also occur. SARS may be associated with other symptoms, including chills, headache, muscular stiffness, loss of appetite, confusion, rash and diarrhoea.
Health experts say the disease has an incubation period of between two and seven days - with three to five days being more common - before victims start showing flu-like symptoms.
How dangerous is it?
The mortality rate appears to be between three to five percent. In Hong Kong, at least, those who are infected invariably develop severe pneumonia, which can cause numerous complications.
Conditions of victims deteriorate very quickly, in as short a period as five days.
How are patients treated?
There is currently no specific cure for the disease. But doctors worldwide have been treating it with ribavirin - an anti-viral drug - and steroids. Doctors say if treated early most patients without other serious illnesses can recover.
How does it spread?
The WHO and Hong Kong experts say the virus spreads through droplets by sneezing or coughing and such direct infection can usually happen within a radius of about one metre.
The virus can also spread indirectly as it can survive outside of the human body for three to six hours. Contact with any object that is tainted by droplets containing the virus could lead to infection if a person then touches their eyes, nose or mouth.
Health experts have not ruled out that it could be airborne, which infinitely raises the contagious nature of the virus and would make it far harder to contain.
How fast does it spread?
The WHO says SARS appears to be less infectious than influenza, and is not highly contagious when protective measures are used. Hong Kong's health chief has said the virus is highly infectious, but can be killed by a solution of common household bleach.
How does the virus travel globally?
The WHO says the speed of international travel creates a risk that cases can rapidly spread around the world.
When an infected person travels, he can spread the virus to other passengers on his flight and also to people at his destination. Authorities around Asia are hunting for passengers who were on about half a dozen flights as they fear that these passengers have been exposed.
Who is most likely to be infected?
Hong Kong experts say the virus is highly concentrated in discharges such as mucous or phlegm when the victim is very sick and in need of urgent medical care. Therefore, the virus has tended to spread primarily to health care professionals treating victims or close family members of victims.
How should infected patients be managed?
The WHO says patients should be placed in an isolation unit. Health care workers and visitors should wear efficient filter masks, goggles, aprons, head covers, and gloves when in close contact with the patient.
Is it safe to travel?
The WHO has not recommended restricting travel to any destination in the world. However, all travellers should be aware of the main symptoms and signs of SARS. People who have these symptoms and have been in close contact with a person who has been diagnosed with SARS, or have a recent history of travel to areas where cases of SARS have been spreading, should seek medical attention and inform health care staff of recent travel.
Travellers who develop these symptoms are advised not to undertake further travel until fully recovered.