SARS
The Toronto Outbreak
April 20, 2003
SARS in Toronto I:
Index Case
• February 23 – A 78 year old woman arrives back in
Toronto from trip to Hong Kong
• February 25 – Develops febrile illness with
anorexia, myalgias, sore throat, cough
• February 28 – Sees MD, given antibiotics
• March 2 – Develops shortness of breath
• March 5 – Dies at home (thought to be heart
attack)
SARS in Toronto 2:
Spread within Household
• Feb 27 - 43 year old son of index case
develops febrile illness (case #2)
• Admitted to Scarborough Grace March 7th, died
March 13th
• March 3 to 12 – all of index case’s other
household contacts develop illness
• 24 year old daughter in law, 5 month old grandson,
34 year old son, 79 year old husband
SARS in Toronto 3:
First spread outside household
• March 5th – Daughter of index case, who
had visited her mother while ill, develops
SARS
• March 9th – Family MD who saw 3 ill family
members on March 6th develops SARS
• March 10th, 13th – Two patients (cases #8
and #9) who spent time in ER observation
area with (Case #2) on March 7/8th
develop SARS
SARS in Toronto 4:
Spread at Scarborough Grace - I
• From case #2 and ill family to 5 ICU nurses
• From case #8 to two paramedics, one firefighter,
four ER staff, one anaesthetist (precautions
initiated in ER; no further transmission except to
anaesthetist performing intubation)
• From case #8’s ill wife to 7 ER visitors, one
housekeeper
• From case #9 (admitted before outbreak
recognized) to at 20 hospital staff and students in
CCU and on medical unit (nurses, MDs, support
staff, radiology, pharmacy, etc.)
SARS in Toronto 5:
Spread at Scarborough Grace - II
• Case #10 – prior exposure only to one
clinic at Scar Grace; admitted 22/3 with
community-acquired pneumonia
– Spread to visitors and at least 2 nurses on
medical unit
SARS in Toronto 6:
Spread to Other Hospitals
• Mount Sinai Hospital
– Case #10 transferred to ICU
– 7 staff infected
• York County Hospital
– Case #9 transferred to ICU
– Wife of case #9, also admitted with #hip (but
had SARS as well)
– 14 staff and one patient infected
SARS in Toronto 7:
Other Spread
• Household contacts of cases
– Estimated risk of unprotected exposure 24%
• Doctors offices when SARS patients were
present
• Persons visiting SARS patients at home
• Funerals of SARS patient at which family
members were ill
• Religious retreats
• Workplace
SARS in Toronto 8:
Transmission “through precautions”
• Two problems:
1. INTUBATION: Three episodes in Toronto hospitals
(March 17 at Scar Grace, March 23 at MSH, April 10th at
SBK) of transmission to all HCW in the room of
patients being intubated
2. PATIENT CARE - over the last month, 6 HCW at 4
Toronto hospitals have acquired SARS despite the use
of SARS precautions
SARS in Toronto 9:
Where are we?
• Community cases remain linked to index case,
but outbreak still expanding
– Intensive public health effort to identify all contacts
and prevent further spread
• Hospital closures and precautions have
substantially but incompletely reduced spread
– SARS precautions enhanced April 19/20
– Intensive investigation into reasons for continuing
transmission, and methods to prevent
Probable and Suspect Cases of SARS in Ontario by Date of Onset
(April 22, 2003 as of 9:00 a.m.)
Number of Cases
Suspect
Probable
25
20
15
10
5
0
Apr-16
Apr-14
Source: Ontario Ministry of Health and Long Term Care, April 22, 2003 as of 9:00am
Apr-12
2) Cases in epi curve includes individuals with known onset dates from all health units with reported cases
Apr-10
1) Total Probable Cases = 136 (1 case with unknown onset date); Total Suspect Cases = 125(2 cases with unknown onset date)
Apr-08
Apr-06
Apr-04
Apr-02
Mar-31
Mar-29
Mar-27
Mar-25
Mar-23
Mar-21
Mar-19
Mar-17
Mar-15
Mar-13
Mar-11
Mar-09
Mar-07
Mar-05
Mar-03
Mar-01
Feb-27
Feb-25
Feb-23
Date of Onset
Notes:
Severe Acute Respiratory Syndrome (SARS)
Toronto (21/04/03)
Exposure
No. (%)
Healthcare worker
95 (36)
Nosocomial patient or visitor
49 (19)
Household contact
77 (29)
Travel
12 (5)
Under investigation
28 (11)
Severe Acute Respiratory
Syndrome (SARS)
Case-Fatality
Age (yrs)
No. cases
No. (%) deaths
<18
17
0
18-35
68
0
36-64
128
3 (2.3)
65
45
11 (24.4)
Total
258
14 (5.4)
SARS in Toronto 10:
What have we learned?
• Cases of SARS that are not suspected
pose the greatest danger to staff
– High index of suspicion and SARS isolation
for febrile patients best protection
• Ill visitors can spread the disease in the
hospital to staff and patients
– Visitor restrictions essential until outbreak is
over
SARS in Toronto 11:
What have we learned?
• Early detection of infection vital so that
precautions can be used to prevent spread
– Fever surveillance in patients and staff critical
to ensuring that transmission is stopped
• Infection control precautions are effective,
but require very careful attention to detail
to be most effective
– Intensive investigation into how to enhance
precautions effectively is underway
SARS in Toronto 12:
What have we learned?
• Intubation, and potentially other coughinducing procedures in the ICU, poses
special risks from some, but not all
patients
– Enhanced precautions being implemented in
ICUs for such procedures
• Some patients much more infectious than
others
– No means to identify these patients currently;
many investigations underway