US Center for Disease Control
SARS ALERT!
GENERAL
INFORMATION
The Illness
What is
SARS?
Severe acute respiratory syndrome (SARS) is a respiratory illness that has
recently been reported in Asia, North America, and Europe. For additional
information, check the World Health Organization's (WHO) SARS Web site or visit
other pages on CDC’s SARS Web site.
What are
the symptoms and signs of SARS?
The illness usually begins with a fever (measured temperature greater than
100.4°F [>38.0°C]). The fever is sometimes associated with chills or other
symptoms, including headache, general feeling of discomfort and body aches. Some
people also experience mild respiratory symptoms at the outset.
After 2 to 7 days, SARS patients may develop a dry, nonproductive cough that
might be accompanied by or progress to the point where insufficient oxygen is
getting to the blood. In 10 percent to 20 percent of cases, patients will
require mechanical ventilation. For more information, see the
MMWR dispatch.
If I were
exposed to SARS, how long would it take for me to become sick?
The incubation
period for SARS is typically 2 to 7 days; however, isolated reports have
suggested an incubation period as long as 10 days. The illness usually begins
with a fever (>100.4°F [>38.0°C]) (see signs and symptoms, above).
What
medical treatment is recommended for patients with SARS?
CDC currently recommends that patients with SARS receive the same treatment that
would be used for any patient with serious community-acquired atypical
pneumonia.
Is the use of ribavirin (or other antiviral drugs) effective in the
treatment of patients with SARS?
At present, the most efficacious treatment regimen, if any, is unknown. In
several locations, therapy has included antivirals such as oseltamivir or
ribavirin. Steroids also have been given orally or intravenously to patients in
combination with ribavirin and other antimicrobials. In the absence of
controlled clinical trials, however, the efficacy of these regimens remains
unknown. Early information from laboratory experiments suggests that ribavirin
does not inhibit virus growth or cell-to-cell spread of one isolate of the new
coronavirus that was tested. Additional laboratory testing of ribavirin and
other antiviral drugs is being done to see if an effective treatment can be
found.
Spread of SARS
How is
SARS spread?
The primary way that SARS appears to spread is by close person-to-person
contact. Potential ways in which SARS can be spread include touching the skin of
other people or objects that are contaminated with infectious droplets and then
touching your eye(s), nose, or mouth. This can happen when someone who is sick
with SARS coughs or sneezes droplets onto themselves, other people, or nearby
surfaces. It also is possible that SARS can be spread more broadly through the
air or by other ways that are currently not known.
How long
is a person with SARS infectious to others?
Information to date suggests that people are most likely to be infectious when
they have symptoms, such as fever or cough. However, it is not known how long
before or after their symptoms begin that patients with SARS might be able to
transmit the disease to others.
Who is
most at risk of contracting SARS?
Most of the U.S. cases of SARS have occurred among travelers returning to the
United States from other parts of the world affected by SARS. There have been
very few cases as a result of spread to close contacts such as family members
and health care workers. Currently, there is no evidence that SARS is spreading
more widely in the community in the United States.
Cause of SARS
What is
the cause of SARS?
Scientists at CDC
and other laboratories have detected a previously unrecognized coronavirus in
patients with SARS. This new coronavirus is the leading hypothesis for the cause
of SARS.
What are
coronaviruses?
Coronaviruses are a
group of viruses that have a halo or crown-like (corona) appearance when viewed
under a microscope. These viruses are a common cause of mild to moderate
upper-respiratory illness in humans and are associated with respiratory,
gastrointestinal, liver and neurologic disease in animals.
How long do coronaviruses survive in the environment?
NEW!
In general, enveloped viruses such as coronaviruses do not last a long time in
the environment. In earlier studies, a different coronavirus was shown to
survive for up to 3 hours on surfaces. At this time, it is uncertain how long
the newly discovered coronavirus associated with SARS can survive in the
environment. In one preliminary study, researchers in Hong Kong found that both
dried and liquid samples of the new coronavirus survived as long as 24 hours in
the environment. Additional studies are under way to examine this important
question.
Can
coronaviruses be found in feces? NEW!
It is not uncommon for respiratory viruses to be found in feces for a period of
time. Some laboratories in the WHO network have reported finding the new
coronavirus in stool specimens. Research is under way in the United States and
other countries to learn more about the presence and concentration of the virus
in different body fluids, including feces. Researchers also are evaluating if
the virus can spread to others through different body fluids.
If
coronaviruses usually cause mild illness in humans, how could this new
coronavirus be responsible for a potentially life-threatening disease such as
SARS?
There is not enough
information about the new virus to determine the full range of illness that it
might cause. Coronaviruses have occasionally been linked to pneumonia in humans,
especially people with weakened immune systems. The viruses also can cause
severe disease in animals, including cats, dogs, pigs, mice, and birds.
Has new
information about coronavirus changed the recommendations for medical treatment
for patients with SARS?
The possibility that
coronavirus is the cause of SARS has not changed treatment recommendations. The
new coronavirus is being tested against various antiviral drugs to see if an
effective treatment can be found.
Is there
a test for SARS?
Several new
laboratory tests can be used to detect the SARS-associated coronavirus (SARS-CoV).
Serologic testing for coronavirus can be performed by using indirect fluorescent
antibody or enzyme-linked immunosorbent assays that are specific for antibody
produced after infection. A reverse transcriptase polymerase chain reaction (RT-PCR)
test also can detect SARS-CoV in clinical specimens, including serum, stool and
nasal secretions. Finally, viral culture and isolation have both been used to
detect SARS-CoV.
What
about reports from other laboratories suggesting that the cause of SARS may be a
paramyxovirus?
Early on in the SARS
investigation, researchers from several laboratories participating in the WHO
network have reported the identification of a paramyxovirus in clinical
specimens from SARS patients. Later findings indicated that a new coronavirus is
the most likely cause of SARS.
The Outbreak
What is the
status of the SARS outbreak in the United States?
NEW!
In the United States, cases of SARS continue to be reported primarily among
people who traveled to affected areas; a small number of other people have
gotten sick after being in close contact with (that is, having cared for or
lived with) a SARS patient while in the United States. Currently, there is no
evidence that SARS is spreading more widely in the community in the United
States.
To minimize the risk for SARS among U.S. residents, the public health system is
taking careful and thorough precautions to stop the spread of SARS. People who
are suspected of having SARS are being isolated from others and getting care.
People arriving from affected parts of the world (who might have been exposed to
SARS) are receiving information about SARS and instructions on what they should
do if they become ill. SARS patients and their contacts are being monitored to
help prevent spread of the disease.
What is
the status of the SARS outbreak outside the United States?
NEW!
Most cases of SARS have been reported from China. In addition, SARS cases have
been reported from more than 20 other countries. Measures to control the spread
of SARS continue to be used in countries worldwide so that the outbreak can be
contained.
Visit WHO's SARS page for daily
updates on case reports in the United States and other countries.
What is
the difference between a “probable” SARS case and a “suspect” SARS case?
NEW!
Suspect SARS cases have fever, respiratory illness, and recent travel to an
affected area with community transmission of SARS and/or contact with a suspect
SARS patient. Probable cases meet the criteria for a suspect case and also have
evidence (e.g., chest X-ray) of pneumonia or respiratory distress syndrome.
How many
people have died from SARS?
Visit
WHO's SARS page for a daily
update of SARS cases and deaths.
What is
the mortality rate for SARS?
NEW!
As of April 23, 2003, a total of 251 SARS-related deaths – or 5.9% of all cases
of SARS – had been reported worldwide. Visit
WHO’s SARS page for a daily update
of SARS cases and deaths.
What is
CDC doing to combat this health threat?
CDC is working
closely with WHO and other partners as part of a global collaboration to address
the SARS outbreak. For its part in this international effort, CDC has taken the
following actions:
As always, CDC is committed to communicating regularly and effectively with public health professionals, elected leaders, clinicians, and the general public.
Travel and Quarantine
What are
CDC's quarantine officials doing to prevent and control the spread of SARS?
CDC's quarantine inspectors or their designees are distributing
health alert cards
to air passengers returning in airplanes either directly or indirectly to the
United States from mainland China; Hong Kong; Taiwan; Singapore; Vietnam; and
Toronto, Canada. The notices inform travelers about SARS and its symptoms and
asks them to monitor their health for 10 days and to see a doctor if they get a
fever with a cough or have difficulty breathing. CDC distributes more than
20,000 health alert notices each day to air travelers returning from the
affected regions. Inspectors also are boarding airplanes if a traveler has been
reported with symptoms matching the case definition of SARS.
WHO has recommended procedures
for pre-departure screening of airline passengers from some countries for
respiratory illnesses or other symptoms of SARS.
What
information about SARS is being provided to people traveling on ships?
SARS information contained on CDC's health alert cards is being provided by the
major shipping associations and the International Council of Cruise Lines to
people traveling on cargo ships and cruise ships at U.S. ports. Inspectors also
are boarding ships if a passenger or crew member has been reported with symptoms
matching the case definition of SARS.
What
does a quarantine inspector do?
Quarantine inspectors serve as important guardians of health at borders and
ports of entry into the United States. They routinely respond to illness in
arriving passengers and ensure that the appropriate medical action is taken.
What is
considered routine health inspections of airplanes or ships versus what is
happening now?
Routine health inspections consist of working with airline, cargo ship, and
cruise ship companies to protect passengers and crew from certain infectious
diseases. Quarantine inspectors meet arriving aircraft and ships reporting ill
passengers and/or crew (as defined in the
foreign
quarantine regulations [pdf]) and assist them in getting appropriate medical
treatment.
What is
the risk to individuals who may have shared a plane or boat trip with a
suspected SARS patient?
Cases of SARS continue to be reported primarily among people who have had direct
close contact with an infected person, such as those sharing a household with a
SARS patient and health-care workers who did not use infection control
procedures while attending to a SARS patient. SARS also has occurred among air
travelers, primarily travelers to and from Hong Kong, Hanoi, Singapore, and
mainland China.
CDC is requesting locating information from travelers who are on flights with
people suspected of having SARS. CDC, with the help of state and local health
authorities, is attempting to follow-up with these travelers for 14 days to make
sure no one develops symptoms consistent with SARS.
Who
actually notifies quarantine officials of potential SARS cases? Is it the crew
of the airplane or ship? The passengers?
Under foreign quarantine regulations, the master of a ship or captain of an
airplane coming into the United States from a foreign port is required by law to
report certain illnesses among passengers. The illness must be reported to the
nearest quarantine official. If possible, the crew of the airplane or ship will
try to relocate the ill passenger or crew member away from others. If the
passenger is only passing through a port of entry on his/her way to another
destination, port health authorities may refer the passenger to a local health
authority for assessment and care.
If I'm
on board an airplane or ship with someone suspected of having SARS, will I be
allowed to continue to my destination?
CDC does not currently recommend that the onward travel of healthy passengers be
restricted in the event that a passenger or crew member suspected of having SARS
is removed from the ship or airplane by port health authorities. All passengers
and crew members may be advised by port health authorities to seek medical
attention if they develop SARS symptoms.
What
does a quarantine official do if a passenger is identified as meeting the case
definition for suspected SARS?
Quarantine officials arrange for appropriate medical assistance to be available
when the airplane lands or the ship docks, including medical isolation.
Isolation is important not only for the sick passenger's comfort and care but
also for the protection of members of the public. Isolation is recommended for
travelers with suspected cases of SARS until appropriate medical treatment can
be provided or until they are no longer infectious.
What
does a quarantine official do if a passenger identified as meeting the case
definition for suspected SARS refuses to be isolated?
Many levels of government (Federal, State, and local) have basic authority to
compel isolation of sick persons to protect the public. In the event that it is
necessary to compel isolation of a sick passenger, CDC will work with
appropriate State and local officials to ensure that the passenger does not
infect others.
Others
Is there
any reason to think SARS is or is not related to terrorism?
Information
currently available about SARS indicates that people who appear to be most at
risk are either health-care workers taking care of sick people or family members
or household contacts of those who are infected with SARS. That pattern of
transmission is what would typically be expected in a contagious respiratory or
flu-like illness.
CDC RECOMMENDATIONS
Personal and Household
What
should I do if I think I have SARS?
If you are ill with a fever greater than 100.4°F (>38.0°C) that is accompanied
by a cough or difficulty breathing or that progresses to a cough and/or
difficulty breathing, you should consult a health-care provider. To help your
health-care provider make a diagnosis, tell him or her about any recent travel
to regions where cases of SARS have been reported and whether you were in
contact with someone who had these symptoms.
What has
CDC recommended to prevent transmission of SARS in households?
CDC has developed
interim infection control recommendations for patients with suspected SARS
in the household. The basic precautions outlined in this document include the
following:
Health-Care Settings
What has
CDC recommended to prevent transmission of SARS in the health-care setting?
Transmission of SARS to health-care workers appears to have occurred after close
contact with symptomatic individuals before recommended appropriate infection
control precautions were implemented. CDC has developed interim infection
control recommendations for the management of exposures to SARS in the
health-care and other institutional settings. Visit
the exposure
guidance page to read these recommendations.
Health-care facilities should be vigilant in conducting active surveillance for
fever or respiratory symptoms among care givers with unprotected exposure to
SARS patients. Health-care workers who develop fever or respiratory symptoms
during the 10 days following an unprotected exposure to a SARS patient should
not report for duty. Such workers should stay home and report symptoms to the
appropriate facility point of contact (e.g., infection control or occupational
health) immediately. Exclusion from duty should be continued for 10 days after
the resolution of fever and respiratory symptoms. During this period, infected
workers should avoid contact with people both in the facility and in the
community.
Exclusion from duty is not recommended for an exposed health-care worker if they
do not have fever or respiratory symptoms; however, the worker should report any
unprotected exposure to SARS patients to the appropriate facility point of
contact immediately.
What
precautions should health-care facilities follow regarding visits by close
contacts of SARS patients?
Close contacts (e.g., family members or other members of the household) of SARS
patients are at risk for infection. Health-care facilities should implement a
system to screen for fever or respiratory symptoms among such contacts who visit
the facility. Close contacts with fever or respiratory symptoms should not be
allowed to enter the health-care facility as visitors and should be educated
about this policy. Health-care facilities should educate all visitors about use
of infection
control precautions when visiting SARS patients and should emphasize the
importance of following these precautions.
Travel and Quarantine
Are
there any travel restrictions related to SARS?
At this time there are no travel restrictions in place that are directly related
to SARS. However, a CDC travel advisory recommends that individuals who are
planning nonessential or elective travel to mainland China, Hong Kong, Taiwan
and Singapore may wish to postpone their trip until further notice. CDC also has
issued travel alerts for Hanoi, Vietnam; and Toronto, Canada, to recommend that
U.S. travelers to any of these places observe precautions to safeguard their
health. For additional information about travel advisories, check
CDC's Travelers' Health site, which
will be updated as necessary.
What is
the difference between a “travel alert” and a “travel advisory” issued by CDC?
NEW!
CDC issues two types of notices to travelers depending on specific situations:
travel alerts and travel advisories. Travel alerts inform travelers of a health
concern in a particular area and provide advice about specific precautions that
should be taken. A travel advisory notifies travelers of potentially more
serious situations and advises that non-essential travel be postponed.
What if I
must travel to a country where there is community spread of SARS? What
precautions can I take?
As with all infectious illnesses, the first line of defense is careful hand
hygiene. As a general rule, it is good practice to wash hands frequently with
soap and water; if hands are not visibly soiled, alcohol-based hand rubs may be
used as an alternative.
To minimize the
possibility of infection, you may wish to avoid close contact with large numbers
of people as much as possible. CDC does not recommend the routine use of masks
while in public areas. For more information, visit
CDC’s website and
specifically read the
Interim Guidelines about Severe Acute Respiratory Syndrome (SARS) for Persons
Traveling to SARS-Affected Areas.
What
should I do if I have recently traveled to a country where cases of SARS have
been reported?
You should monitor your own health for 10 days following your return. If you
become ill with a fever of more than 100.4°F [>38.0°C] that is accompanied by a
cough or difficulty breathing or that progresses to a cough and/or difficulty
breathing, you should consult a health-care provider. To help your health-care
provider make a diagnosis, tell him or her about any recent travel to regions
where cases of SARS have been reported and whether you were in contact with
someone who had these symptoms.
CDC has
recommended guidelines for medical aircraft that transport SARS patients. Should
commercial airlines also follow these guidelines?
No. This guidance (available at
this page)
is intended specifically for air medical transport (AMT) service providers that
use specialized aircraft to transport SARS patients. It should not be
generalized to commercial passenger aircraft. These interim recommendations for
AMT are based on standard infection control practices, AMT standards, and
epidemiologic information from ongoing investigations of SARS, including
experience from transport of 2 patients during this outbreak. Specific
guidelines for airline crew and flight personnel of commercial aircrafts are
available at
this page. CDC also has developed
interim guidance
for cleaning of commercial passenger aircraft after a flight with a suspected
SARS passenger.
from US Dept of Health-Center for Disease Control