SARS Epidemiology, Infection Control and Lessons Learned from Toronto

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SARS Epidemiology, Infection Control and
Lessons Learnedfrom Toronto
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Stats to date (June 18,2003)

• Total probable cases of SARS 11/1/2002
  6/18/2003
• 8,465 worldwide
• 29 countries
• 801 (9.5) deaths

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Stats to date (June 18,2003)

• U.S reported to date
• Total 401
• 75 (18) probable cases
• 334 (82) suspect cases
• 42 states and Puerto Rico
• Tested
• 45 of 75 probable 8 (18) positive
• 136 of 334 suspect None positive

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Confirmed U.S. Cases

• 7 had travel history to areas with documented or
  suspected community transmission with in 10 days
  prior to illness
• Hong Kong, Toronto, Singapore, Taiwan
• All were on travel advisory list at the time of
  transmission
• 1 case was spouse of lab-confirmed case that had
  traveled to Hong Kong

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SARS in Toronto IIndex 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)

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SARS in Toronto 2Spread within Household

• Feb 27 - 43 year old son of index case develops
  febrile illness (case 2)
• Admitted to Hospital A March 7th, died March 13th
• March 3 to 12 all of index cases other
  household contacts develop illness
• 24 year old daughter in law, 5 month old
  grandson, 34 year old son, 79 year old husband

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SARS in Toronto 3First 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

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SARS in Toronto 4 Spread at Hospital A - 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 8s ill wife to 7 ER visitors, one
  housekeeper
• From case 9 (admitted before outbreak
  recognized) to 20 hospital staff and students in
  CCU and on medical unit (nurses, MDs, support
  staff, radiology, pharmacy, etc.)

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SARS in Toronto 5 Spread at Hospital A - II

• Case 10 prior exposure only to one clinic at
  Hospital A admitted 22/3 with community-acquired
  pneumonia
• Spread to visitors and at least 2 nurses on
  medical unit

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SARS in Toronto 6Spread to Other Hospitals

• Hospital B
• Case 10 transferred to ICU
• 7 staff infected
• Hospital C
• Case 9 transferred to ICU
• Wife of case 9, also admitted with hip (but had
  SARS as well)
• 14 staff and one patient infected

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SARS in Toronto 7Other 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

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Toronto SARS 2/23/03 6/10/03
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SARS II Source of Exposure
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Transmission to HCWs

• Hong Kong
• 138 cases, 85 (62) in HCWs
• Toronto (first part of outbreak)
• 144 cases, 73 (51) in HCWs
• 40 nurses, 19 doctors, 41 others
• Toronto (second wave of outbreak)
• 74 cases, 29 (39) in HCWs
• As more is learned about transmission and
  appropriate PPE less transmission in the Health
  care setting

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SARS Case-Fatality
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SARS in TorontoWhat have we learned?

• Cases of SARS that are not suspected pose the
  greatest danger to staff and others
• 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

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SARS in TorontoWhat 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

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SARS in Toronto 8Transmission Woos

• Two problems
• 1. INTUBATION Three episodes in Toronto
  hospitals (March 17 at Hospital A, March 23 at
  Hospital B, April 10th at Hospital D) 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

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SARS in Toronto 9Where were they?

• Community cases remained linked to index case,
  but outbreak after expanding waned
• Intensive public health effort to identify all
  contacts and prevent further spread
• 5 Hospitals and 3 long-term care facilities
  closed 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

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SARS in TorontoWhat have we learned?

• Intubation, and potentially other cough-inducing
  procedures in the ICU, poses special risks from
  some, but not all patients
• Enhanced precautions are needed for such
  procedures
• Some patients much more infectious than others
• No means to identify these patients currently
  many investigations underway

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Infection Control for SARS in U.S

• Standard Precautions with addition of eye
  protection for all patient contacts
• Contact Precautions (gowns and gloves) to enter
  room
• Airborne Precautions
• Negative pressure room, if not available, private
  room with door shut
• N-95 respirator

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Additional Recommendations

• Triage areas Need to be ask patients with fever
  and/or respiratory symptoms about travel history
  or contact with SARS cases
• Triage areas needs to know where to look for
  latest travel information (www.cdc.gov SARS,
  then travelers)
• Any patient with fever and/or respiratory
  symptoms with possible epidemiologic link should
  be given surgical mask
• If cant wear mask, given tissues to cover mouth
  and nose when coughing/sneezing
• Placed into examine room quickly

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Additional Recommendations

• Does every case of suspect or Probable SARS need
  to be admitted to a hospital?
• If patient is not sick enough to be admitted, do
  not need to admit for Infection Control reasons
  only
• If patient has home environment where precautions
  can be followed than can go home with public
  health coordination
• If unstable home environment may need to admit
  until stable situation can be worked out

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Role of Infection Control

• Infection control should be notified when
  patients are being evaluated for SARS
• If ruled out then no intervention needed (or
  coordinate with public health to follow outcome)
• If still possible, help coordinate with public
  health
• If send home - for contact tracing and
  arrangements for follow-up and home isolation
• If admitted contact tracing, hospital isolation
  followup and coordination with employee health
  for HCW follow-up.

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Infection Control Related to Aerosal-Generating
Procedures

• Examples of procedures
• Intubation
• Procedures that stimulate coughing
• Bronchoscopy
• Suctioning
• Positive pressure ventilation (BiPAP, CPAP)
• High frequency oscillatory ventilation

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Infection Control Related to Aerosal-Generating
Procedures - 2

• Limit opportunities for exposure
• Limit procedures that are not absolutely
  medically necessary or replace with alternative
• Example avoid nebulized mediation substitute
  metered dose inhalers with spacer
• Use appropriate sedation for intubation and
  bronchoscopy
• Use anti-tussive and anti-emetic medications
• Limit number of HCWs present during high-risk
  procedures
• Use most experience personnel for procedure

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Infection Control Related to Aerosal-Generating
Procedures - 3

• Use Airborne isolation environment for procedures
• If not available
• use private room
• away from other patients
• Increase air exchanges if possible (may be able
  to create negative pressure that way)
• Avoid recirculation of air, if air is
  recirculated use HEPA filtration
• Keep doors closed

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Infection Control Related to Aerosal-Generating
Procedures - 4

• Use filters of ventilation exhaust valves
• Additional PPE
• Optimal PPE for preventing transmission during
  high risk procedures is not known
• Gown full body suit may be considered
• Gloves single pair
• Eye protection with snug fitting goggles
• May add face shield over goggles
• N-95 mask
• Fit tested and fit checked
• May consider PAPR or full facepiece elastomeric
  negative pressure (non-powered) respirators with
  N, R, and P100 filters

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Infection Control Related to Aerosal-Generating
Procedures - 5

• Additional instructions for HCW
• Take care to contain area of contamination
• Avoid touching face and PPE with contaminated
  hands/gloves
• Use care in removing PPE
• Hand Hygiene critical after removal of PPE

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Additional Things

• Cleaning
• Handling of Specimens
• Handling of post-mortem
• Coordination with public health
• Influenza Vaccination

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Acknowledgement

• Many thanks to my Canada colleagues for sharing
  their experience as well as their slides