sars: a view from a public health department
DESCRIPTION
TRANSCRIPT
“SARS in the City”: Infection control lessons
Bonnie Henry MD MPH FRCP(C), CSTE
Buffalo, 10 June 2009
City of Toronto
Severe Acute Respiratory Syndrome Symptoms include:
◦ a fever of more than 38 degrees C ( 100.4 degrees F)
◦ muscle aches, severe fatigue, severe headache
◦ dry cough, shortness of breath◦ positive chest x-ray
What is SARS?
Where it began..
21 February, 2003 a Chinese Doctor from Guandong checks into room 911 at the Metropole hotel….
Christian et al. Submitted to CID October
2003
Phase 1: Mar 13 - Apr 20 Phase 2: May 20 - Jun 24 438 cases across Canada (225 in
Toronto)◦ 44 deaths (38 in Toronto)◦ 222 hospitalized, 50 in Intensive Care Units◦ 50% in health care workers (4 deaths)◦ cluster of 31 cases associated with a religious
group◦ no significant community spread
A Brief Chronology
Figure 2. Cases investigated for SARS and contacts identified as requiring quarantine
0
10
20
30
40
50
60
15-Mar-0
3
25-Mar-0
3
4-Apr-03
14-Apr-03
24-Apr-03
4-May-03
14-May-03
24-May-03
3-Jun-03
13-Jun-03
Date of report to Toronto Public Health
Num
ber o
f inv
esti
gate
d ca
ses
0
1000
2000
3000
4000
5000
6000
7000
8000
Num
ber o
f con
tact
s re
quir
ing
quar
anti
ne did not meetcase definition
met SARS casedefinition
contactsrequiringquarantine
*Cases are graphed as stacked bars comprised of persons investigated that met and did not meet SARS case definition.
† Contact numbers do not include healthcare workers who were placed in work quarantine (n=5743). The maximum number of persons requiring quarantine at any one time was 6995.
Average incubation period 4.7 days (range 1-12)
66% of cases were female, Average age was 49 years (5mos-99years)
Average age of those who died 71 (38-99) Only 3 deaths in persons less than 50 Mean time from onset of symptoms to death
19 days (1-78)
Epidemiology
Index Case Case A
Mr. D
(Mother) (Son)
Mr. P
Mr. P’swife
Mr. R?
24 persons
9 persons
21 persons
15 persons
7 persons
Infection Control Directives Screening, recognition of cases Administrative controls: screening of staff,
limiting visitors etc. PPE: initial recommendations based on
uncertainty BUT not able to lower level when more known
Issue of Fit Testing of N95 Respirators Dealing with changes: occurred frequently,
communications was difficult, led to mistrust
How do you stop an outbreak when: Agent is unknown Incubation period uncertain Mode of transmission not entirely clear No diagnostic test No prophylaxis No vaccine No treatment
R0 = population density x infectivity x time
Outbreak Control
Quarantine◦ not used > 50 years in Canada◦ “invented” work quarantine
Used combination of◦ quarantine/work quarantine with daily or
twice daily assessment◦ active surveillance with daily assessment◦ self-monitoring with periodic follow-up◦ day 10 follow-up and counselling
Isolation/Quarantine
Isolation/Quarantine Linking ill with
assessment centres Provision of needed
supplies for monitoring and infection control (thermometers, masks etc)
Very difficult physically, emotionally, mentally
Linkage of symptomatic contacts to assessment centres
“Voluntary” quarantine -
issues
Issued 27 Section 22 orders
under HPPA Challenges of determining if
someone is at home by phone e.g. cell phones, internet, lack of phone
Government financial support
Very difficult mentally, physically, emotionally and financially
Infection Control Continuum Public Health in the
community (schools, daycares, restaurants, gatherings etc)
Public Health and sometimes hospital based ICPs manage outbreaks in Long Term Care
Hospital epidemiologists, ICPs and infection control programs in Acute Care Facilities
What role does OHS have or should have in IPC?
What about the regulators (Ministry of Labour)
Where do private physician offices fit in? What about prehospital and home care, who
provides them with IPC guidance? What about other community based
providers? (radiology clinics, OT, Physio, dialysis centres etc)
Beyond the Continuum
Key role in communication with the public Can be liaison or link between healthcare
facilities, first responders and the community
Limited expertise in hospital infection prevention and control issues
Have legal authority for many restrictive actions
Public Health Role
Need to invest in infection control Need to invest in occupational health
resources Need to define roles and responsibilities of
federal, provincial and local public health authorities
Far more stakeholders need to be connected than we used to think (schools, business, shelters, jails, transit etc.)
Lessons Learned
Lessons from SARS
It is easier to control disease than fear
CoordinationCollaborationCommunication
Clarity
=Confidence
Influenza: Why have we worried?
Novel virus in avian/animal population
Susceptible human population
Infectious to humans Highly pathogenic
BUT no efficient human to human spread
Will this lead to a pandemic…
F/P/T communication much improved but still needs work
IC guidance developed for H5N1 avian flu Still having issues with communications to
community providers
Influenza A H1N1(Swine)
NEJM (Trifonov V et al. Geographic dependence, surveillance, and origins of the 2009 influenza A (H1N1) virus. N Engl J Med 2009 May 27 [Epub ahead of print].
IPC guidance developed rapidly BUT delayed at the federal government for translation
Approval process still not worked out completely
Facilities, HCWs filled the void with CDC and others (Web 2.0)
Led to difficulty when guidance differed (especially around N95 respirator use)
Fit testing became an impediment to safety
H1N1 and IPC
Things to Think About for the Fall SARS was about containment
◦ Mostly spread in hospitals
Influenza is about capacity◦ Mostly spread in the community◦ HCWs will get sick whether they use N95s or not!
Need to reinforce this is INFLUENZA not SARS
IPC guidance needs to reflect the evolving situation
Thank you