Information about Pandemic Influenza

Harvey Kayman, MD, MPH, PHMO IIICalifornia Department of Public Health

Division of Communicable Disease ControlImmunization Branch

Objectives

• Learn about Pandemic Influenza

• Learn how to prevent, protect, and mitigate

• Learn what challenges we face

The three criteria of a Pandemic

• Ability to isolate a new influenza virus from a human.

• Can be spread from human to human.

• Spreads worldwide.

An influenza A pandemic:

• is a global disease outbreak.

• occurs when there is little or no immunity to that strain of influenza in the human population.

• causes serious illness, and can sweep through populations.

Seasonal versus Pandemic Influenza

• Drift: Slight changes-H3N2 to new H3N2Seasonal Influenza

• Shift: Big changes-• H5N1 appears in Humans= Pandemic Influenza

The AVIAN H5N1 virus has raised concerns about a potential human

pandemic because:

• It is especially virulent.

• It is being spread by migratory birds and transported domestic poultry.

• It can be transmitted from birds to mammals and in some limited circumstances to humans.

Migratory water birds

Domestic birds

The origins of influenza A virus

Humansand other animals

Human influenza A viruses start as avian (bird) influenza viruses

Rapid Worldwide Spread

• The entire world population is susceptible to a pandemic with a new strain of virus.

• Countries can delay arrival of the virus.

Community-Based Interventions

1. Delay disease transmission and outbreak peak2. Decompress peak burden on healthcare infrastructure3. Diminish overall cases and health impacts

DailyCases

#1

#2

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Days since First Case

Pandemic outbreak:No intervention

Pandemic outbreak:With intervention

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Pandemics are not new:

• Pandemics since, at least, the sixteenth century.

• The 1918 “Spanish flu,” is generally regarded as the most deadly disease event in human history.

History of PI Deaths in the 20th century

• 1918 PI-500,000 U.S. deaths and up to 40 million deaths worldwide.

• 1957 PI-70,000 U.S. deaths and 1-2 million deaths worldwide.

• 1968 PI-34,000 U.S. deaths and 700,000 deaths worldwide

History of PI in the 20th century

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Flu after WW I

• While most deaths from seasonal influenza occur in the very young or very old, the deaths from this pandemic were primarily in those aged 15-35, with 99% of deaths in those under 65.

Case-fatality rates (panel C, solid line 1918-19; dotted line-usual seasonal flu

Waves of severe illness

• Pandemics occur in waves of sickness, and the virus may increase in potency between outbreaks.

• The mortality rate of the pandemic of 1918-1919 increased tenfold with the arrival of the second wave.

• Waves generally last two to three months.

Three pandemic waves: weekly combined flu and pneumonia

mortality, U K, 1918–1919 (21).

Characteristics

• The influenza virus mutates and evolves often during Pandemics and between seasons.

• Illness is more severe if the virus attaches to lung tissue and causes an extreme immune response.

Contagiousness

• The typical period between infection and the onset of symptoms is two days

• Persons who have become ill may transmit the infection as early as one day before the onset of symptoms

• The risk of infection is greatest the first two days of illness

• Children play a substantial role in the transmission of influenza

Potential Risk Factors for Humans

• Slaughtering, • De-feathering, or • Preparing sick poultry for cooking; • Playing with or holding diseased or dead

poultry;• Handling fighting cocks or ducks that

appear to be well; and• Consuming raw or undercooked poultry or

poultry products NEJM 2008;358:261-73.(1/17/08)

High death rates may be largely determined by four factors:

• (1) the number of people who become infected;

• (2) the virulence of the virus; • (3) the underlying characteristics and

vulnerability of affected populations; and

• (4) the degree of effectiveness of preventive measures.

H5N1 Cases and Deaths as of May, 2008 WHO

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Total

CasesDeaths

Potential need for care in USA

Characteristic Moderate Severe

# Ill 90 million 90 million

# in OPD 45 million 45 million

# need Hospital 1 million 10 million

# need ICU 125,000 745,000

# Ventilators 65,000 745,000

# of Deaths 200,000 2 million

Citizens develop strategies for action In Kansas City 2008

• Most people know very little about pandemic flu.

• Workshop participants grappled with the question of how to inform people of the need to prepare for pandemic flu in a way that would encourage action.

• One KC Voice Pandemic Flu Citizen Engagement Project 2008

Barriers to preparation

• The need to earn a paycheck. • No sense of urgency, and no perceived

incentives for action.• Few neighborhood, church and school

leaders are involved in preparing for pandemic flu.

• People will disregard health department advisories if they feel they need to care for children or parents.

• One KC Voice Pandemic Flu Citizen Engagement Project 2008

Protective and Mitigating responses

• Cross sector planning and collaboration including governmental preparedness

• Cross boundary planning and collaboration

• Adopt unified command structure, and vocabulary using Incident Command System

• Improve and expand training systems• Legal issues and legal system

Obtain and Track Impact of the Pandemic (Surveillance):

• Detect initial cases of PI • Identify virus and treatment susceptibility

in Laboratory• Improve electronic data reporting system

to track: Attack rates Rates of influenza hospitalization Case fatality rates Isolated and quarantined persons, treatment and

support.

Protective and Mitigating responses

• Vaccine

• Antiviral medications

• Other medications to reduce inflammation ??

• Personal protective equipment; Masks and respirators, etc.

ImmunizationN Engl J Med 2008;358:261-73.

• Safe and immunogenic inactivated H5 vaccines have been developed.

• Decisions regarding the use of vaccine before a pandemic and stockpiling require complex risk–benefit and cost–benefit analyses:

• Effects on the seasonal capacity of vaccine production, timing and cause of the next influenza pandemic are unknown, and

• Unclear if immunization of large populations could have adverse consequences.

Anti-Viral Drug treatment

• Early treatment with oseltamivir (Tamiflu™) is recommended,

• Rx may improve survival,

• Optimal dose and duration of therapy uncertain.

• Mortality remains high despite oseltamivir;

• Late initiation of therapy a major factor.•

N Engl J Med 2008;358:261-73.

Initiate Social Distancing:

• Dismiss students

• Cancel large gatherings

• Restrict mall usage and business activities.

• Restrict travel on public transportation.

Collins SD, Frost WH, Gover M, Sydenstricker E: Mortality from influenza and pneumonia in the 50 largest cities of the United States First Edition Washington: U.S. Government Printing Office 1930.

1918 Death Rates: Philadelphia v St. Louis

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Communications:

• Improve risk communication, both to and from constituents.

• Improve interoperable communications networks between State, public health, health care community, EMS,

9-1-1, emergency management, public safety etc.

Protective and Mitigating responses

• Prepare for security and law enforcement challenges.

• Prepare for ethical challenges and the “least unfair” resource allocation.

• Prepare for spiritual challenges on population and personal levels.

Protective and Mitigating responses

• Anticipate concerns and needs of at-risk individuals and populations.

• Attend to Mental Health/Disaster mental health system design.

Assessment and Concerns:

• Assess available work capacities, commodities, equipment, and personnel for all sectors.

• Improve Health Care system SURGE capacity

• Create protocols to expand healthcare services

Ports of Entry

• Develop a port of entry (POE) communicable disease response plan for locations with a Quarantine Station --which includes ill passenger assessment and isolation procedures

• Ready legal orders for detention, isolation, quarantine, and conditional release of passengers or crew members

• Prepare for serious mental health challenges at Ports of Entry.

Community disease containment• WHO recommendations:

– advise ill people to remain at home– use measures to increase social distance– mask use by the public should be based

on risk; routine mask use should be permitted, but not required

– hand hygiene and respiratory hygiene/cough etiquette should be strongly encouraged

Community disease containment

• Although nonpharmaceutical interventions may be the only interventions available for community disease containment early in a pandemic, the effectiveness of such interventions has not been well studied

Health Care Systems Overloaded

• Infection and illness rates may soar. • A substantial percentage of the world’s

population will likely require some form of medical care.

• Nations are unlikely to have the staff, facilities, equipment and hospital beds needed to cope with large numbers of people who suddenly fall ill.

Medical Supplies Inadequate

• The need for vaccine is likely to outstrip supply.

• The need for antiviral drugs is also likely to be inadequate early in a pandemic, so will need to be “allocated”.

• Difficult decisions will need to be made regarding who gets antiviral drugs and vaccines.

All Supplies Inadequate

• A pandemic can create a shortage of hospital beds, ventilators and other supplies.

• A pandemic can create a shortage of all commodities; especially fuel, food, and essentials.

• Surge capacity at non-traditional sites such as schools may be created to cope with demand.

Economic and Social Disruption

• Travel bans, student dismissal, closure of businesses and cancellations of events could have major impact on communities and citizens.

• Care for sick family members and fear of exposure can result in significant worker absenteeism.

Economic costs

• According to the Congressional Budget Office, an outbreak on the scale of the 1918 pandemic could result in a loss of 5% of gross domestic product, or a national income loss of approximately 600 billion dollars.

A Framework for Planners Preparing to Manage Deaths

• It is clear increased numbers of natural deaths in a potentially short period of time will place considerable pressure on all local Public Services providers.

• Systems for receiving and disseminating information will need to be robust and capable of moving at a fast pace-tell it all, tell it truthfully and tell it quickly.

• The Home Office: Mass Fatalities Section (Pandemic Influenza Consultation) London• http://www.ukresilience.info/upload/assets/www.ukresilience.info/flu_managing_deaths.pdf

Trigger Points for Different Ways of Working

• Scale of increased deaths.• Limited storage space at local mortuaries and

funeral parlors • Absenteeism. • How to complete death certificates.• Political policy formulation and

implementation; the activation of emergency regulations.

• Combination of pressure points.

Holding and Burial sites

• Limited capacity to hold the deceased prior to funerals at hospital mortuaries, public mortuaries, in private homes and funeral parlors.

• Use of refrigerated vehicles and trailers?• Cemetery managers should plan for alternative

ways of providing graves.• Move to provision of common graves?• Common graves should be deep enough to

allow for additional family burials.

Time to prepare

• While no one can state with complete certainty that a pandemic will occur, the signs point to it being a prudent time to begin careful and thorough preparation.

Business Continuity Planning and Pandemic Influenza in

Europe (Coker report 2008):• Demonstrate Leadership &

Commitment • Develop Business Continuity Plans

(BCP) • Identify Risks and Quantify Impacts• Provide Information, education and

communication

Business Continuity Planning and Pandemic Influenza in

Europe (Coker report 2008):

• Attend to Occupational Health and Safety

• Review Human Resource Policies• Assess the resiliency of supply

chain• Ensure continued access to

financial resources

COLLABORATION AND COORDINATION (Coker report 2008):

• Sharing of best practices with business partners, the community and within the industries must be encouraged

• Public-private collaboration must be facilitated

COLLABORATION AND COORDINATION (Coker report 2008):

• The allocation and commitment of specific resources to pandemic preparedness and response have to be considered as a crucial component of the planning

PUTTING PLANS INTO ACTION (Coker report 2008):

• Whenever it is possible, every employer should test the effectiveness of their plans

• RECOVERY PLANNING • There is an urgent need to encourage

organizations to prepare for the recovery and this area should be addressed in all organizational guidance

• An Analysis of Independent Sector and National Governments’ Guidance. Alexandra Conseil, Sandra Mounier-Jack and Dr. Richard Coker (London School of Hygiene and Tropical Medicine (LSHTM), 6/12/08) www.lshtm.ac.uk/ecohost/flupanbcp

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Area 1. Leadership and Commitment Area 2. Risk Assessment and Impact Quantification

Area 3. Information, Education and Communication Area 4. Occupational Health and Safety

Area 5. Human Resources Issues Area 6. Operational Continuity

Area 7. Putting Plans into Action Area 8. Recovery Planning

Area 9. Collaboration and Coordination

WHO tests capacity to respond

• Exercise in Vancouver, B.C. (6/08) was designed and conducted to test how well the WHO can use the new International Health Regulations.

• A global health treaty that requires countries to report disease outbreaks that might have international ramifications.

Los Alamos mathematical model uses anomaly detection

• Identifies subtle changes in epidemiological data.

• Uses far less data over shorter time frames, not huge amounts of data for accuracy,

• Can be used on data from a handful of infected people in a remote village.

General Resources

• Links to Additional Information

• http://www.pandemicflu.gov/ (managed by the Department of Health and Human Services)

• http://www.cdc.gov/flu/avian/ (managed by the Centers for Disease Control and Prevention)

Resources for this presentation

• http://www.medicalreservecorps.gov/File/MRC_Pandemic_Influenza_Planning_Guidance.pdf

• http://www.flcourts.org/gen_public/emergency/index.shtml).