Transcript Public Health Guidance for Community

SARS Timeline
Nov 16 ‘02
Feb 11 ‘03 Feb 28
First cases
retrospectively
Recognized,
Guangdong,
China
March 11
March 12
March 19
March 27 April 5
Hong Kong
and Vietnam
report outbreaks in
hospital
workers
Acute
respiratory
reported in
Guangdong
by China
MOH
WHO
issues
travel
advisories
Reported
in U.S. and
Europe
April 17 April 28
Sequence
of suspected
agent, a
coronavirus,
established
China
coverup
admitted;
SARS
made top
priority
WHO
issues
global
alert
First
SARS
case –
Vietnam
April 9 April 14
India
SARS
First
SARS in
Africa
Vietnam
containing virus
(WHO)
Case Distribution of SARS Worldwide
ERSI, May 2003
ERSI, May 2003
Effect of Travel and Missed Cases on the
SARS Epidemic
Spread from Hotel M, Hong Kong
Canada
Guangdon
g Province,
China
F,G
A
F,G
18 HCW
11 close
contacts
A
Hong Kong
SAR
95 HCW
Hotel M
Hong
Kong
A
H,J
H,J
B
>100 close contacts
B
Vietnam
37 HCW
21 close
contacts
K
K
Ireland
0 HCW
I, L,M
C,D,E
C,D,E
Singapor
e
34 HCW
37 close
contacts
I,L,M
United
States
1 HCW
SARS Hotspots (as of May 28, 2003)
# Probable Cases
# Deaths
China
Hong Kong
Taiwan
Singapore
Canada
United States
Vietnam
Philippines
Other Countries
5322
1728
596
206
148
65
63
12
62
321
269
76
31
26
0
5
2
4
Total
8202
734
Number of SARS Cases Reported over
Time (China)
250
200
150
100
50
10
5,
08
5,
06
5,
04
5,
02
5,
30
4,
28
4,
26
4,
24
4,
4,
22
0
Symptoms of SARS
•
•
•
•
Cough
High fever
Severe pneumonia
Difficult to distinguish from other
respiratory diseases in early stages
Incidence Difference across
Different Age Groups (China)
35.0
（1/1,000,000）
29.2
30.0
25.0
21.5
18.7
20.0
18.0
16.1
16.5
6 0 -
7 0 -
15.0
10.0
7.2
5.0
1.6
0.0
0-
1 0 -
2 0 -
3 0 -
4 0 -
5 0 -
CDC, 2003
Fatality Rates of Different Age Groups
30.0
28.0
26.3
25.0
20.0
17.6
15.0
10.0
10.0
5.0
5.0
3.0
0.0
0.0
0-
10-
0.9
0.0
20-
30-
40-
50-
60-
70-
80-
CDC, 2003
Etiology
SARS Diagnostics
Key Messages
•
•
•
•
SARS diagnostic assays are sensitive and specific, but may
not provide definitive diagnosis early in the illness
Changes in the quantity, type, and timing of specimens
collected may improve detection of SARS-CoV infection
Rapid and accurate diagnosis of other respiratory pathogens
associated with SARS-like illness may help rule out SARSCoV infection and calm public fears
Interpretation of test results must take into consideration
possibility of false positives and negatives; a clear strategy
to minimize such possibilities and to confirm test results are
essential
CDC, 2003
Peiris: personal communication
Prevention of SARS
Definitions of Quarantine
 Isolation
• Separation and restricted movement of ill persons
with contagious disease
• Often in a hospital setting
• Primarily individual level, may be populations
 Quarantine
• Separation and restricted movement of well persons
presumed exposed to contagion
• Often at home, may be designated residential facility
• Applied at the individual or community level
 May be voluntary or mandatory
CDC, 2003
Modern Quarantine
A collective action for the common good
predicated on aiding individuals infected or
exposed to infectious agents while protecting
others from the dangers of inadvertent exposure
Public good
Civil liberties
Meeting needs of individuals infected and exposed is paramount
CDC, 2003
Key Issues to Consider
•
•
•
•
•
•
•
•
•
•
Surveillance
Clinical evaluation
Infection control measures
Patient isolation
Engineering controls
Exposure evaluation
Staffing needs and personnel policies
Access controls
Supplies and equipment
Communication
CDC, 2003
SARS Mysteries
Origin of SARS – animal reservoirs?
Is coronavirus the etiologic agent?
• Cases without antibody
• Non-cases with antibody
SARS Mysteries (continued)
What proportion of exposed persons
develop clinical disease and death?
• Proportion of exposed, infected and
asymptomatic
Are there asymptomatic carriers?
• Reports of cases without known source of
exposure
SARS Mysteries (continued)
What causes “super shedders”?
• Host characteristics; e.g., age
• Agent characteristics – “virulent strain”
Is pathology caused by the virus or the
response to the virus?
• AIDS patients appear to be resistant to SARS
SARS Mysteries (continued)
Will SARS reappear in the fall?
• SARS is transmitted through the respiratory
route. These diseases, like influenza, tend to
have a season cycle with resurgence in the late
fall, winter and early spring
Will SARS Re-emerge?
 Potential sources of re-emergence
• Animal reservoir
• Humans with persistent infection
• Unrecognized transmission in humans
• Laboratory exposure
 SARS most likely to recur outside U.S.
• Well-established global surveillance is important
to recognition of first case