Unit 4 Surveillance and Notification of Pandemic Flu

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Unit 4 - Surveillance and Notification of
Pandemic Flu
Training Kit for Pandemic Influenza
Prepared by Infectious Disease Control Training
Centre, Hospital Authority Infection Control
Branch, Centre for Health Protection, Department
of Health
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By the end of this unit, you will be familiar
with
Objectives

• the case definition of avian influenza
• the surveillance and notification mechanism of
  pandemic flu
• the investigation and control measures

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Three essential components to control an outbreak
include

• Early case identification
• Isolation of suspect/probable cases
• Tracing and monitoring close contacts of all
  suspect/probable cases identified

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Surveillance ??
Reporting ??
Contact tracing ????
Isolation ??
Diagnosis ??
Follow up ??
Treatment ??

-
Pre-exposure ???
Prophylaxis ????
Post-exposure ???
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Surveillance

• Ongoing data collection
• Interpretation and dissemination of data
• Enable the development of evidence based
  interventions

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Case definitions
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WHO Case Definition
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HKSAR CENO Case Definition of Influenza
A(H5N1) Last updated on 14 Sep 2006
Source https//ceno.chp.gov.hk/casedef/casedef.js
p
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HKSAR CENO Case Definition of Influenza
A(H5N1) Last updated on 14 Sep 2006
Source https//ceno.chp.gov.hk/casedef/casedef.js
p
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HKSAR CENO Case Definition of Influenza
A(H7)/(H9) Last updated on 14 Sep 2006
Source https//ceno.chp.gov.hk/casedef/casedef.js
p
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Surveillance System

• Designated AE,GOPD
• Symptoms surveillance program
• e-FLU surveillance
• Health care workers surveillance

S2, E1 and E2

• Enhance surveillance and triage of ILI with
  epidemiological link
• Laboratory surveillance for Pos. Flu A with
  epidemiological link
• Enhance surveillance of laboratory workers
  handling clinical
• specimens

Alert Response Level and S1

• Notifiable diseases and outbreak reporting system
  (NDORS)
• Staff early sickness alert system (SESAS)
• Sentinel surveillance in GOPC and private doctor
• Investigation and reporting of hospital
• outbreak/ unusual clustering

On going
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Surveillance systems for Pandemic Flu

• Ongoing surveillance system
• Report suspected Avian Influenza to CHP
• Notifiable diseases and outbreak reporting system
  (H5, H7, H9 influenza) (NDORS)
• Staff Early Sickness Alert System (SESAS)
• Investigating and reporting of hospital
  outbreak/unusual clustering
• Sentinel surveillance in GOPCs and Private
  doctors

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Reporting Criteria for Human Influenza A (H5, H7,
or H9) Infection

• Clinical Criteria
• Person with acute respiratory illness,
  characterized by fever (temperature gt38?) and
  cough and/or sore throat, OR
• Person with unexplained pneumonia, OR
• Person died of unexplained acute respiratory
  illness

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Reporting Criteria for Human Influenza A (H5, H7,
or H9) Infection (Continue)

• Epidemiological Criteria
• One of more of the following exposures in the 7
  days prior to symptoms
• onset
• Close contact (within 1 metre) with a human case
  of Influenza A (H5, H7 or H9) (e.g. caring for,
  speaking with, or touching)
• Exposure (e.g. handling, slaughtering,
  defeathering, butchering, preparation for
  consumption) to poultry, wild birds, or their
  remains, or to environments contaminated by their
  faeces in a country / area with H5N1 infections
  in animals or humans in the last month
• Consumption of raw or undercooked poultry
  products in a country/ area with H5N1 infections
  in animals or humans in the last month
• Close contact with a H5N1 infected animal other
  than poultry or wild birds (e.g. cat or pig)
• Handling samples (animal or human) suspected of
  containing Influenza A (H5, H7 or H9) virus in a
  laboratory or other setting.

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2. Under Alert Response Level and S1

• Enhance surveillance and triage of ILI with
  epidemiological link
• Laboratory surveillance of positive flu A with
  epidemiological link
• Enhance surveillance of laboratory workers
  handling clinical specimens
• Symptoms surveillance program for staffs involved
  in poultry culling (S1)

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3. Under S2, E1 and E2

• A. General
• Monitoring mechanisms for antiviral usage and
  stock level in HA hospitals
• Ad hoc surveillance programs as advised by CHP
• B. Patients
• Designated AE ,GOPC coding monitoring program
  for ILI
• e-FLU for surveillance ,contact tracing,
  communication and administrative purpose (HA)
• At least daily temperature check (including
  inpatients, outpatients and day patients) and
  report of clustering of phenomenon to infection
  control team
• C. Health Care Workers
• Encourage daily body temperature check
• Report any fever(38OC), respiratory symptoms,
  and/or conjunctivitis for 1 week after last
  exposure to avian influenza-infected patient
• Data should be entered into the SESAS
• D. Visitors
• Advise to take temperature check by themselves

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Reporting Flow Chart at Hospital level
Surveillance
Patient enter triage with fever/- respiratory
symptoms
No
Reassess precaution
Alternate diagnosis
History of TOCC
Unusual case/cluster in wards
Yes
Admission to isolation ward
Infection control measures

• Upon completing risk assessment,
• ICT should notify
• CCE
• CHP
• CCID

Notify hospital ICT
Review cases and contact tracing
HCE, ICT, and/or CHP would assess the situation
and for investigation
CCID would evaluate the situation consider the
need to convene COCT
Follow up and timely update/report to
CCE/CHP/CCID
Notification
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Investigation and Control Measures
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When a local case of human avian/ novel influenza
infection occurs

• Isolate the patient for clinical treatment
• Field investigation by CHP to
• Identify source of infection
• Trace the contacts
• Ascertain the mode of spread
• Advise on disinfection

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Definition
Close Contact

• Close contacts refer to the presence of an
  individual within 1 metre with a suspected or
• probable case of novel influenza (e.g. caring
  for, speaking with, or touching the case) so
• that there is a high chance of contact with
  respiratory secretions or body fluids of the
• case.

Management

• May be put under quarantine
• -antiviral treatment will be prescribed
• -medical surveillance for 7 days (or latest
  knowledge of incubation period of
  
• influenza virus) from the last contact of the
  case

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Definition
Social Contact

• Social contacts are contact cases that do not
  fulfil the definition of close contacts

Management

• Will be put under medical surveillance for 7 days
  (or latest
• knowledge of incubation period of avian/ novel
  influenza
• virus)

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Other Public Health Measures

• Measures to increase social distance when human-
• to-human transmission is confirmed, for
  examples
• -Closure of schools and public places
• -Stopping public gathering
• -Curtailing non-essential activities and services
• Culling
• -If the source of infection of the case is
  suspected
• to be related to local poultry

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End of Unit 4