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Learn about the origins, characteristics, and historical impact of Pandemic Influenza to enhance awareness and preparedness. Discover preventive measures, challenges, and strategies for response through cross-sector collaboration and surveillance.
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Information about Pandemic Influenza Harvey Kayman, MD, MPH, PHMO III California Department of Public Health Division of Communicable Disease Control Immunization 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.
The origins of influenza A virus Human influenza A viruses start as avian (bird) influenza viruses Migratory water birds Humans and other animals Domestic birds
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.
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
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.
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.
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 • DevelopBusiness 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