Preparing for the Next

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Preparing for the Next Influenza Pandemic
Susan E. Tamblyn, MD, DPH, FRCPC Medical Officer
of Health Perth District Health Unit
University of Toronto
November 15, 2002
contact tamblyn_at_pdhu.on.ca
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Learning Objectives
At the end of this educational session,
participants should be able to 1. describe
influenza pandemics and their potential
impact 2. discuss the role played by
international, federal, provincial and local
agencies in planning for and responding to an
influenza pandemic 3. discuss current status of
strategies for surveillance, vaccines and
antivirals, health services planning, emergency
response, and communications 4. create an
effective local pandemic plan
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Why Focus on Pandemic Planning?

• next influenza pandemic could to be associated
  with high mortality, morbidity and societal
  disruption worldwide
• emergency will be complex, rapidly evolving and
  provoke public alarm
• too late at its onset to take many steps to
  lessen its impact
• planning will enhance capacity to respond to
  other public health emergencies (including
  bioterrorism) and improve response to annual flu
  epidemics

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Influenza 101

• of the 3 influenza types (A, B and C), only
  influenza A is associated with pandemics
• influenza A subtypes are classified by their
  surface
• proteins haemagglutinin (H) and neuraminidase
  (N)
• 15H and 9N subtypes known
• humans affected mainly by H subtypes 1-3
• aquatic birds are the reservoir for all
  subtypes

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Where Do Influenza Epidemics Originate?
evidence suggests most epidemics emerge from
China close mingling of ducks, pigs, humans
allows reassortment of viruses minor changes
called drift if big enough result in new
epidemic at unpredictable intervals, major
changes called shift occur that result in a
pandemic (3-4 per century)
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Source Nature Medicine 1998 41122-3.
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Source Nature Medicine 1998 41122-3.
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Setting for a Pandemic
emergence of an influenza A subtype with a new
/ different haemagglutinin high proportion of
susceptible people in the population high
person-to-person transmission of the new virus,
with accompanying human disease
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History of Influenza Pandemics
Year Influenza A Strain 1847 ? 1889 -
1890 H2N2 1899 - 1900 H3N2 1918 -
1919 H1N1 Spanish flu 1957 H2N2 Asian flu
1968 H3N2 Hong Kong flu (1977 H1N1)
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Observations from Previous Pandemics
1-6 months warning from first global alert to
local outbreaks 1st wave often out-of-season,
lasts 6-8 weeks (peak at 3-4 weeks) 2nd wave
3-9 months later may be more severe 3rd wave
may also occur
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Pandemic Epidemiology II

• many hospitalizations and deaths will be in
  young, previously healthy people
• percentage of deaths lt age 65
• 1918 99
• 1957 36
• 1968 48
• pneumonia deaths predominated in 1918
• (both primary viral and secondary bacterial)
• in 1957 1968, cardiovascular and other
  complications accounted for about half of deaths

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Pandemic Mortality
No. of deaths Death rate Worldwide Canada pe
r 100,000 pop.
1918-19 40-50 m 50-60,000 218 1957 gt 1
m 7,000 22 1968 3,000 14
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Pandemic Impact in Ontario

• up to 8 million people will be infected (up to
  75)
• 1.6 - 4 million will be clinically ill (up to
  38)
• 0.7 - 1.8 million will require outpatient care
• (up to 17)
• 12 - 32,000 will require hospitalization
• (up to 0.3)
• 3,000 - 12,000 deaths (up to 0.1)

(Extrapolated from CDC estimates)
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1976 Swine Flu Lessons (H1N1)

• decision-making process
• mass vaccination program
• unexpected vaccine adverse events (GBS)
• need for domestic vaccine security
• led to first Canadian pandemic plan

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1997 Hong Kong Incident Lessons (H5N1)

• avian source significant lab biosafety
  issues control issues
• difficulties in vaccine production
• communications were over-riding concern
• wake-up call worldwide for pandemic planning

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Discussion Questions
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WHOs Role in Influenza

• 50 years of surveillance activities
• - 4 WHO collaborating centres
• - 112 national influenza labs
• - collaborating centre for animal influenza
• viruses
• determine composition for annual vaccines
• Pandemic Preparedness Plan (1999)
• WHO Global Strategy (2002)

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Components of the Global Agenda
A. Strengthen epidemiological
virological surveillance B. Increase knowledge on
health economic burden of disease C. Increase
influenza vaccine use D. Accelerate national and
international action on pandemic preparedness
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• Accelerate national and international action on
  pandemic preparedness
• 1. increase awareness of the need for pandemic
  planning
• 2. accelerate development and implementation of
  national pandemic plans
• 3. enhance use of vaccine and antivirals in the
  interpandemic period
• 4. develop strategies for use of vaccines and
  antivirals and securing adequate supplies in a
  pandemic
• 5. advocate research on pandemic viruses,
  vaccines, antivirals and other control measures

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WHOs Role in a Pandemic

• task force to assist in viral and epidemiologic
  studies
• heightened surveillance through WHO network
• official declaration of the pandemic
• preparation of seed strains and reagents for
  vaccine development
• advice on response, including use of vaccines
  and antivirals

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WHO Response Phases
Phase 0 - interpandemic activities Phase 0,
Preparedness Level l - new strain in human
case Phase 0, Preparedness Level 2 - human
infection confirmed (2 or more) Phase 0,
Preparedness Level 3 - human transmission
confirmed Phase 1 - onset of pandemic Phase
2 - regional multi-regional epidemics Phase
3 - end of 1st pandemic wave Phase 4 - 2nd or
later waves Phase 5 - end of the pandemic
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Some Global Realities

• pandemic could emerge in China where
  surveillance and info sharing is still weak
• rapid dissemination through air travel
• developing countries will be as hard hit as
  elsewhere maybe worse
• no antivirals unless stockpiled
• vaccines will not be available for 6 or
  more months

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Global Realities II

• countries with vaccine manufacturers may
  nationalize supplies
• only 8 countries have domestic vaccine
  manufacturer
• current production serves lt 5 of world
  population
• about 30 countries have pandemic plans

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Vaccine Antiviral Strategies

• Key points from recent WHO consultation
• expect shortages of both vaccines and antivirals
• wise use follows goals and priorities chosen by
  a country
• probably need 2 doses of vaccine for a naïve
  population
• monovalent vaccine to be used
• options to improve immunity include whole cell
  vaccines and use of adjuvants

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Vaccine Antiviral Strategies II

• antiviral use is totally dependent on stockpiles
• options are prophylaxis (PEP or during full
  pandemic wave) and/or treatment
• need to avoid amantadine / rimantadine for
  treatment
• issues of sharing with have not countries

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Discussion Questions
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Pandemic Planning in Canada

• ongoing activity for 20 years
• major revisions under way since Hong Kong
  incident
• in 1997
• federal/provincial planning meetings held in
  1999 and 2000 provincial / local planning
• F/P/T agreement led to establishment of PIC
  (Pandemic Influenza Committee) and funding of a
  vaccine strategy
• challenge now to integrate with bioterrorism
  planning

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Canadian Pandemic Influenza Plan

• Plan will have three sections
• preparedness section developed by CIDPC
• now out for review
• response being developed by CIDPC and CEPR
• recovery not yet developed

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Framework for Planning Response

• Key sections
• Surveillance
• Antivirals
• Health Services Emergency Planning
• Emergency Planning Response
• Communications
• Plan describes components and key planning
  activities (checklists) and has annexes and
  guidelines.

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Canadian Pandemic Response Goal

• to reduce influenza morbidity and mortality and
  minimize societal disruption among Canadians by
  providing access to appropriate prevention, care
  and treatment

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Surveillance

• objectives are to detect emergence, spread and
  impact of novel strains in Canada
• may include special studies at borders and major
  points of arrival
• early need to identify population susceptibility
  to new strain
• both virologic and activity surveillance,
  including outbreak investigation and real-time
  mortality tracking

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Surveillance Local Responsibilities

• advance planning for activity monitoring
• eg sentinel physicians, school or workplace
• absenteeism, emergency room visits
• virologic surveillance will be directed by the
  province to include resistance monitoring
• need rapid flow and analysis of data
• local epidemiologic picture triggers other
  response eg antiviral prophylaxis, hospital
  response

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Vaccines

• Canada has a pandemic contract with Shire to
  develop capacity to produce enough vaccine for
  whole population (includes continuous
  availability of fertilized eggs)
• expedited approval mechanisms and clinical trial
  protocols are under development
• need to monitor uptake, adverse events and
  vaccine effectiveness
• national priorities for vaccine use

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Priority Groups for Vaccination

• Health care workers
• Essential service workers
• Persons at high risk of severe or fatal outcomes
• long term care facilities
• NACI high risk
• seniors
• children lt 2
• pregnant women
• 4. Healthy adults
• 5. Children 2-18 years

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Vaccines Local Responsibilities

• plan to vaccinate whole population with 2 doses
  a month apart
• might or might not be able to use family doctors
  as vaccinators (not during wave of illness)
• develop generic mass vaccination plan, using
  universal flu experience and Waterloo and
  Alberta reports
• plan tracking of uptake, adverse events

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Antivirals

• Canadas antiviral strategy and stockpile is not
  yet approved
• antivirals will likely be our only intervention
  for the first wave
• antiviral distribution will be controlled,
  probably through public health
• need to monitor uptake, adverse events,
  resistance and effectiveness

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Priority Groups for Antivirals

1. treatment of persons hospitalized for flu
2. treatment of high risk persons in community
3. prophylaxis of health care workers
4. outbreaks in LTCF
5. prophylaxis of essential service workers
6. prophylaxis of other hospitalized patients
7. prophylaxis of high risk persons in community
8. treatment of ill persons (not high risk)

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Assumptions

• prophylaxis is for six weeks
• triggered by arrival of flu in local area
• treatment is for five days
• and only for persons ill lt 48 hours
• amantadine is used only for prophylaxis (to
  prevent development of resistance)
• neuraminidase inhibitors are used for treatment

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Antivirals Local Planning

• develop mass distribution plan for public health
  controlled drug (can be generic anthrax etc)
• potential scenarios
• - hospitals dispense for patient and health care
  worker prophylaxis (pharmacy committee control)
• - Health Unit or community pharmacy clinics for
  ESWs and other HCWs
• - selected pharmacies for Rx courses

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Health Services Emergency Planning

• problems no surge capacity, shortage of
  personnel at time of high demand and increased
  risk of infection
• extensive clinical guidelines have been
  developed
• clinical management
• triage
• resource management
• mass casualties
• non-traditional sites and workers
• infection control

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Health Services Local Planning

• ideal is integrated response involving doctors,
  clinics, hospitals and CCAC
• establish plans for community clinics / triage
  sites
• establish hospital expansion plans / alternate
  sites
• clarify communication between health services
  and public health

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Community Control Measures

• general advice for public
• emphasis on personal and hand hygiene
• community mask use felt ineffective
• effectiveness of closure of public places,
  including schools needs more study
• (modeling ?)

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Communications

• federal communications plan still under
  development
• expect templates, fact sheets, key messages,
  guidelines, etc
• secure web site will be used
• essential to harmonize with all levels of
  government consistent messaging

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Communications Local Planning

• develop public health emergency communications
  plan (not just for pandemics)
• identify stakeholders and communication
  strategies to reach them
• dispelling rumors and myths

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Emergency Planning and Response

• at all levels, need to dovetail with the
  emergency response system already in place
• eg Emergency Management Ontario
• maintaining essential services should be their
  key responsibility
• highlight differences from other emergencies
  prolonged emergency, little outside help,
  affects people not infrastructure

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Emergency Response Local Planning

• engage local municipalities and emergency
  control groups in pandemic preparedness
• want pandemic annex for local plans
• need way to coordinate county-wide or Health
  Unit-wide response
• establish triggers for moving to ECG control
  (vs HU led) and declaring a local emergency

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Creating a Local Plan

• Various approaches can work. Steps include
• raising awareness
• developing a plan to plan
• framework / timetable
• with appropriate stakeholders, developing
  details for each component
• writing up the plan
• exercises to test components of the plan

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Planning Problems

• working with committees vs internal planning
• whos in charge?
• - what type of coordinating committee?
• - relationship with municipal ECGs
• finding time / talent to develop the plan
• lack of provincial plan

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Unresolved Provincial Issues

• hospital preparedness
• licensing issues / use of alternative
  practitioners
• stockpiling / distribution issues
• decisions on who will immunize
• surveillance / reporting requirements

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Discussion Questions