Larry D' Jecha MD MPH Health Officer

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Larry D. Jecha MD MPHHealth Officer
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Pandemic Influenza
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Why The Concern About Pandemic Influenza?

• Influenza pandemics are inevitable naturally
  recur at more-or-less cyclical intervals
• Can cause
• High levels of sickness and death
• Drastic disruption of critical services
• Severe economic losses
• There will be little warning time between the
  onset of spread of a pandemic and its arrival in
  the U.S.

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Why The Concern About Pandemic Influenza?

• Outbreaks occur simultaneously in many areas
• Impacts will last for weeks to months
• Pandemics disproportionately affect younger,
  working-age people
• Current avian influenza outbreak in Asia

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Influenza

• Disease of swine, birds, horses and man
• Orthomyxoviridae (single strand RNA)

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Typical Flu Symptoms

• Fever (gt102º F)
• Muscle and Joint Aches and Pains
• Dry Cough
• Runny Nose
• Sore throat
• GI symptoms in children and infants

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Spreading the Flu

• Droplet spread
• Infectious
• Adults 1 day prior to symptoms to about 5 days
  after onset
• Children and immunocompromised much longer
• Incubation
• 1 to 4 days

Image Source Human Biology, Starr and McMillan
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Death from Flu

• Viral Pneumonia
• Rapid destruction of lung tissue
• Secondary bacterial pneumonia
• Disrupted lung tissue
• Bodys defense mechanisms impaired
• Encephalitis
• 36-thousand Americans die each year

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Influenza A (H5N1) Pneumonia
Hien. NEJM 20043501179
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Avian Flu

• Two types common in birds
• Low pathogenic
• Mild symptoms
• Ruffled feathers, poor egg laying
• High pathogenic
• Deadly 90-100 mortality rate
• Surviving birds shed virus in their droppings for
  10 days after recovery
• Subtype H5N1

Colorized transmission electron micrograph of
Avian influenza A H5N1 viruses (seen in gold)
grown in MDCK cells (seen in green).
http//phil.cdc.gov/phil/quicksearch.asp - 1841
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Avian Flu (H5N1)

• Since 2003, there have been small clusters of
  avian flu in SE Asia.
• Millions of birds have been killed in an attempt
  to control the disease.
• As of December 30, 2005
• 142 human cases, 74 deaths

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Avian Flu

• Majority of human cases have been linked to close
  contact
• Home slaughter, de-feathering, butchering and
  preparation for cooking
• Traditionally slaughter and eat birds when signs
  of illness appear

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Avian Flu Concerns in SE Asia

• Barnyard flocks are kept close to the family
  home.
• Domestic flocks often mingle freely with wild
  birds.
• Flocks often scavenge for food, entering
  households or sharing areas where children play.

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Avian Flu Concerns in SE Asia

• Pigs also kept close to families
• Pigs are transported and sold in open markets
  where exposure to the bird flu and human flu
  could occur
• Pigs in Indonesia have been found carrying H5N1,
  but did not show signs of illness

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As and Bs, Hs and Ns

• Flu is classified by the RNA core
• Type A or Type B influenza
• Further classified by surface protein
• Hemagluttin (H) 15 subtypes known
• Neuraminidase (N) 9 subtypes known
• Only Type A had pandemic potential

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Antigenic Drift

• Natural mutation of surface proteins over time to
  evade the immune system.
• Occurs in all types of viruses.
• Guessing what the changes will be, to allow for
  vaccination of public.

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Potential Source of Shift
15 HAs 9 NAs
Non-human virus
Human virus
Reassortant virus
Source CDC Influenza Branch
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Pandemic Influenza

• Any new type of flu with the ability to
• Infect humans
• The avian virus apparently has this ability.
• Cause serious illness in humans
• Be easily spread among the human population.
• So far, the bird virus lacks this vital talent.
• Not seasonal it can occur at any time.
• Currently, there is no pandemic flu.

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Pandemic Influenza

• Reassortment of RNA
• Two flu strains swap RNA
• A Shift occurs that allows the transmission
  from Avian to Human populations
• A Novel Virus in a Naïve Population

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Worse than WW II?

• The Spanish flu of 1918-1920
• At least 20 million deaths world wide
• At least 500,000 deaths in the US
• One of the reasons the War to End all Wars
  ended
• Unique W Shaped Age Distribution

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US Infectious Disease MortalityThe Impact of
Influenza and AIDS
Armstrong. JAMA 199928161
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More Flu Pandemics

• Other Flu Pandemics in the 20th Century
• Asian Flu of 1957-58
• 70K US Dead
• Hong Kong Flu of 1968-69
• 40K US Dead

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Projected Impact

• Typical Pandemic attack rate 15 35 of the
  population
• More death than usual under 65 years old
• Strains all aspects of the health care system

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Ways to Stop Pan Flu

• When there is a Novel virus
• Culling/vaccinating the bird flocks
• When there is person to person spread
• Quarantine/Isolation
• Antiviral medications
• Development of vaccine
• When there is widespread dissemination
• Antiviral medications
• Vaccine

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Containment Strategies

• Infection Control
• HICPAC Practice Guidelines
• Possibility of Designated Hospitals
• Isolation/Quarantine
• DOH in Advisory Role
• LHO in Counties
• DGMQ at International Ports of Entry

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Antiviral Medication

• Tamiflu will be the drug of choice
• Prophylaxis
• Daily dosing for length of pandemic
• Not recommended option by CDC
• Treatment
• Must Start Within 2 Days Of Onset
• Twice daily dosing for 5 days

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Problems in Creating a Vaccine

• Isolate the virus
• The virus has not mutated yet to the form that
  affects humans easily
• Convert it to a vaccine
• Produce enough vaccine for 300M people
• Current egg method not sufficient
• 300 M doses of vaccine requires 3.5 M eggs
• Avian flu strains are lethal to chicken embryos
  requiring genetic modification
• Do it in 6 months
• Virus continues to mutate

A scientist uses eggs in the laboratory to
cultivate bird flu vaccine at CSL's flu facility.
http//www.smh.com.au/news/national/race-for-a-vac
cine/2005/10/21/1129775959991.html
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Public Health Goals in a Pandemic Protecting the
Publics Health

• Limit death and illness
• Preserve continuity of essential government and
  business functions
• Minimize social disruption
• Minimize economic losses

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Public Healths Role in a Pandemic

• Leadership Role in Emergency Response
• Disease Tracking and Control
• Health System Coordination
• Community Education
• Communications

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The New WHO Pandemic Phases
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The New WHO Pandemic Phases
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National Influenza Plan

• Intended to provide national, state and local
  guidance
• Acknowledges, but does not address
• Vaccine Manufacture and Distribution
• Antiviral Manufacture and Distribution
• Priority Group for Vaccine and Antivirals

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Surveillance

• Priority in any Pandemic Response
• Surveillance Intensifies throughout pandemic
  stages
• Novel Flu made a reportable disease
• Surveillance Year Round
• Increased Lab Testing

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Pandemic Impact Health Care System

• Extreme staffing shortages
• Shortage of beds, facility space
• Shortage of key supplies (ventilators, drugs)
• Hospital morgues, Medical Examiner and mortuary
  services overwhelmed
• Extreme demands on social and counseling services
  
• Demand will outpace supply for months

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Health Care Systems

• Alternate Care Sites
• Triage/Referral Points
• Neighborhood Emergency Health Centers
• Points of Distribution
• Staffing
• Sustained Operations and Surge Capacity
• Volunteers, Retirees, etc.

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Pandemic Impact Infrastructure

• Significant disruption of transportation,
  commerce, utilities, public safety and
  communications
• Limited to no assistance from State and Federal
  governments due to nation-wide impact

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Pandemic Impact Businesses

• High absenteeism
• Psychological impacts on workforce will be
  extreme
• Social distancing efforts may dramatically change
  hours of operation or close businesses
  temporarily
• Economic losses small businesses at greatest
  risk

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Business Planning

• Start planning now
• Identify essential functions
• Consider telecommuting and flexible work hours
• Promote Cough Etiquette
• Encourage people to stay home when sick
• Get your annual flu shots

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Protecting Yourself and Others

• The single best way to protect against the flu is
  to get vaccinated each fall.
• There are two types of vaccines
• The "flu shot"an inactivated vaccine (containing
  killed virus) that is given with a needle,
  usually in the arm.
• The nasal-spray flu vaccinea vaccine made with
  live, weakened flu viruses that do not cause the
  flu.

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Protect yourself and others!

• To help stop the spread of germs,
• Cover your mouth and nose with a tissue when you
  cough or sneeze.
• If you don't have a tissue, cough or sneeze into
  your upper sleeve, not your hands.
• Put your used tissue in the waste basket.

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• Clean your hands after coughing or sneezing
• Wash with soap and water.or
• Clean with alcohol-based hand cleaner.

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Be Prepared

• Have an emergency plan for your family
• Have an emergency survival kit
• Include supplies for at least three days
• Follow social distancing recommendations

• Courtesy King County Office of Emergency
  Management

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What We Need From You

• Engage in business continuity planning
• Share resources and capabilities
• Share information about absenteeism to support
  tracking of disease
• Cooperate with social distancing measures
• Partner with us