The World Health
Organization calls Severe Acute Respiratory Syndrome, or SARS, a new
communicable disease that is a global health threat. More than 480 people
have recently fallen ill from the potentially fatal disease, which has
spread around the globe by air travel.
Here's a look at what is and isn't known about the mysterious disease:
What are the symptoms?
The disease spreads from person to person. It often begins with a high
fever, headache and sore throat. Other possible symptoms include loss of
appetite, confusion, rash and diarrhea. Not everyone has reacted the same
The WHO said doctors are on the lookout
for those symptoms with:
a fever over 38 C AND
cough, shortness of breath, difficulty
close contact with someone diagnosed
with SARS or a history of travel to affected areas, including Toronto,
Vancouver, Guangdong province in China, Hong Kong, Singapore and Hanoi,
The respiratory symptoms appear two to
seven days after exposure.
The disease has been compared to
influenza and pneumonia, but for lack of a better description, WHO has
called the disease SARS. The Centers for Disease Control and Prevention
notes the definition may include people who don't actually have the
syndrome, but it is a starting point for investigation.
What causes SARS?
Researchers don't know whether bacteria
or a virus causes SARS, and it may take several weeks to find out.
Researchers in the U.S. have seen a coronavirus, one of the viruses
that causes the common cold. They say SARS could be caused by a
combination of viruses. It is too early to tell.
Microbiologists in Hong Kong believe they have identified a test to
diagnose SARS, which they are perfecting.
"It is most likely to be viral, but that is not a certain thing at this
point," said Dr. Andrew Simor, head of microbiology and a specialist in
infectious diseases at Toronto's Sunnybrook and Women's College Health
Sciences Centre. Tests have failed to show it is influenza. The leading
candidate has been human metapneumovirus, a family of microbes that can
cause measles, mumps and canine distemper. Experts say the findings are
based on electron microscope images, which aren't definitive. Other tests
such as genetic profiling are needed to confirm the findings.
What are the risks?
"If someone is in close contact with one of the probable cases they are at
greater risk," said Dr. Colin D'Cunha, Ontario's Public Health
Commissioner, on March 23. "For members of the general public, the risk
appears to be otherwise slim and near zero." He added there is no evidence
it spreads through casual contact.
Probable cases are people showing symptoms who have recently travelled to
Asia or have been in close contact with other SARS patients. Suspect cases
show symptoms, but have no travel or contact history. Dr. Jay Keystone, a
travel and tropical disease specialist with the University of Toronto,
said close contact is needed with someone who is infected. Ninety per cent
of cases have been in unprotected health care workers, who have had direct
contact with respiratory secretions (sneezes, coughs, nasal fluids) of
SARS patients. He added SARS is moving quickly around the world because of
air travel, but it isn't spreading rapidly within the community.
Where did SARS originate?
WHO has reported hundreds of cases in Hong Kong and Vietnam since
February. An outbreak of pneumonia with similar symptoms struck Guangdong
province in China last November and was brought under control in
Doctors in Hong Kong are focusing their investigation on a hotel where
seven guests contracted the ailment from a Chinese professor and carried
it to Vietnam, Singapore and Canada.
No one knows how the disease spread in the hotel. Health officials have
speculated the professor sneezed or coughed by an elevator. One expert
pointed to the hotel's air conditioning system, but none of the hotel
workers have become sick.
What does the Toronto quarantine
Several health care workers at Scarborough Grace Hospital in Toronto's
east end were exposed to SARS before they knew to take precautions. Access
to the hospital has been restricted.
As a precaution, on March 26 Toronto's medical officer of health
recommended everyone who has visited Scarborough Grace Hospital since
March 16 should stay in their home for 10 days from the time of the visit.
Their family members may go to work or school, but must wear a mask when
at home and in contact with those who are at risk of infection.
Hospital visitors are unlikely to have had direct contact with SARS
patients and they have "a very low risk of exposure." Health officials
said isolating cases is a priority, and the extraordinary measures are the
only way to manage the disease and protect people. Anyone who may be a
contact of a SARS case through Scarborough Grace and has symptoms or
concerns can call the Toronto Public Health Hotline at (416) 338-7600 for
Infected health workers and their family members have been quarantined,
meaning they cannot go to school or work, buy groceries etc.
Starting March 27, a community assessment clinic will open at the Women's
College Campus of Sunnybrook and Women's College Health Sciences Centre.
People with symptoms of SARS can go to the clinic to be assessed in an
area isolated from the rest of the hospital.
What are governments doing?
On March 25, SARS became a reportable, virulent, communicable disease in
Ontario. The change allows public health officers to quarantine infectious
people and their family members for up to 10 days to track the disease and
prevent it from spreading.
The Ontario government has set up an around-the-clock command centre to
co-ordinate information on the spread of the virus. People with general
questions about SARS can call Telehealth Ontario at 1-866-797-0000 to
speak to a registered nurse.
Canadian, provincial and local health officials are working together to
enhance surveillance and look for additional cases, including those
arriving on international flights. Sick passengers are assessed in
separate rooms and promptly taken from the airport to hospital.
Laboratories around the world, including the National Microbiology
Laboratory in Winnipeg, are trying to determine the origins and cause of
the disease. On the other side of the Pacific, health officials in
Singapore have quarantined more than 700 people who may be at risk. In
Hong Kong, officials have called for all schools to be disinfected.
Children with infected family members must avoid classes for a week.
What about travel?
"Given the uncertainties of the current situation, Health Canada believes
it is prudent to await the outcome of national and international control
measures before undertaking travel to these destinations," the advisory
Health Canada also warns travellers that health care services may not be
up to handling SARS. For example, the only adequate hospital in Hanoi has
Health alert notices are handed out to all passengers arriving on
international flights from all destinations other than the United States.
The notices tell passengers to be on the look out for symptoms that may
develop within 10 days of arriving, such as fever, cough, and breath. If
so, they should seek immediate medical attention. Hospital staff are
taking travel medical histories.
In Hong Kong, airplane passengers have become ill. The World Health
Organization said on March 25 that air travel is safe, but its scientists
are looking closely at the growing number of cases in Hong Kong to see
whether it is more contagious than thought.
"We would want to be sure that it was people sitting next to that person
and not the ventilation system in the airplane which was spreading the
disease," said Dr. David Heymann, head of communicable diseases at WHO.
"We have no evidence of the latter right now."
Health investigators have followed thousands of passengers who flew with
SARS-infected travellers and did not become sick.
How are patients being treated?
In Toronto, those suspected of having SARS are being quarantined in rooms
with a controlled air supply, said Dr. Simor. Anyone who goes into the
room wears a special mask to filter out pathogens, as well as gloves and a
gown. Hand washing is also important. Keystone said the simple masks
people are wearing in Hong Kong would stop large droplets, but masks
wouldn't work against fine, aerosol droplets. In Toronto, Simor said,
patients are being treated with broad-spectrum antibiotics (in case it is
caused by an as-yet unrecognized bacteria), and two antiviral drugs. One
antiviral drug fights influenza and the other is a broad-spectrum
antiviral that may have helped patients in Hong Kong