Session 7, Section 2 Public Health

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Session 7, Section 2Public Health

• Rick Bissell, PhD
• Tom Kirsch, MD, MPH

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Role of Public Health

• Public health is crucial to helping catastrophe
  victims survive the impact of the event and in
  helping the public regain sufficient personal
  physical energy and stability that they can
  recover from their losses and actively
  participate in the community recovery and
  rehabilitation processes. In some cases, e.g.
  pandemics, the catastrophe may be primarily a
  public health event.

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Basic Vocabulary

• Public health The scientific and service
  discipline that deals with the health of
  populations, including, among other things,
  investigating the causes of good and poor health,
  applying scientifically validated interventions
  to protect or improve health, and educating the
  public regarding good personal health practices.

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Basic Vocabulary - 2

• Epidemiology The discipline within public health
  that investigates the causes and pathways of
  diseases and injuries, as well as their
  distribution within a population.
• Surveillance The monitoring of behavior. It can
  be the behavior of an infectious disease, a
  population (e.g. birth control or sanitation
  practices), or other health conditions (e.g.
  diabetes, arthritis, hunger).

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Key Points

• Health of the population, not an individual
  patient.
• Uses scientific methods (epidemiology and
  surveillance) to identify and intervene in health
  problems (e.g. epidemics).

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Discussion Point

• There are many more rescuers (EMTs, firefighters,
  SAR personnel, etc.) than emergency managers.
  There are many more physicians and nurses
  practicing medicine than there are personnel
  practicing public health. How might the roles of
  emergency managers be similar to those of public
  health professionals?

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Infectious Disease Vocabulary

• Etiology The causes and pathway of a disease.
• e.g. the bacteria or virus and its behavior
• Infectious disease control The use of
  epidemiologic, public health, and medical tools
  to limit or control the spread of infectious
  diseases.
• e.g. quarantine infected persons

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Infectious Disease Vocabulary - 2

• Endemic A disease or health condition that has a
  long-term presence in a population at a
  relatively stable level.
• e.g. the common cold
• Epidemic A disease or health condition that
  rises above expected levels.
• e.g. the annual Influenza outbreak
• Pandemic An epidemic that affects the entire
  world, or substantial portions of it.
• e.g. the 1918 Influenza pandemic

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Infectious Disease Vocabulary - 3

• Ways to Prevent Disease Spread
• Immunity The ability of an individuals immune
  system to fight off an invading microbe and avoid
  infection.
• This can be natural or with the use of vaccines

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Infectious Disease Vocabulary - 4

• Herd immunity When there are enough immune
  individuals in a population (usually gt80) then
  that specific infection cannot easily spread and
  cause an outbreak.
• Herd immunity can be from having a prior
  infection in a population, or by mass
  vaccinations.

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Infectious Disease Vocabulary - 5

• Social distancing The strategy of limiting
  disease spread by limiting public gatherings.
• e.g. Closing schools and churches, or staying at
  least 3 feet from other people.
• Quarantine The strategy of limiting disease
  spread by holding ill or exposed individuals out
  of contact with the public.

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Infectious Disease Vocabulary - 6

• Isolation The strategy of limiting disease
  spread by holding an ill individual in a
  controlled-access room.
• e.g. Isolation rooms in hospitals use special air
  filtration systems and protective clothing.

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Disease Control Mechanisms

• How diseases spread
• Waterborne droplet (e.g. respiratory diseases)
• Fecal-oral or hand-to-mouth (e.g. diarrheal
  diseases)
• Water- and Foodborne
• Sexual contact (e.g. STDs and HIV)
• Fomites (microbes on inanimate surfaces)
• Blood exposures (e.g. HIV, hepatitis C)
• Vectors (insects, rats, airplanes, etc)
• Ignorance and bad choices!

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Disease Control Mechanisms -2

• Disease control
• Epidemiologic investigation to determine causes,
  mechanisms of spread, extent of spread.
• Vaccination, use of medication to induce herd
  immunity, treat ill individuals.
• Social distancing, quarantine, isolation, reduce
  vectors.
• Treatment of individuals to reduce their
  infectivity (ability to spread the infection).

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Review

• Public Health and epidemiology are scientific
  methods to prevent or reduce the spread of
  illness in a population.
• Endemic and epidemic infectious diseases are the
  leading cause of death worldwide.
• There are specific tools used to reduce the
  spread of infections. For example

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WASH YOUR HANDS!

• COVER YOUR COUGH!

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Discussion Question 2

• In an epidemic scenario, why is it not sufficient
  to just treat everybody who comes down with the
  disease?

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Catastrophes Public Health

• The catastrophe can be caused by a health
  emergency. e.g. pandemics.
• Catastrophes with a non-health etiology can
  strongly affect population health status.
  Examples hurricanes, earthquakes, tsunamis,
  drought, sea level rise/flooding, etc.

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Catastrophes Public Health - 2

• Sample primary health impacts
• Hurricanes injuries from falling and flying
  debris drowning
• Earthquakes injuries from collapsing structures
  and landslides
• Tsunamis drowning, traumatic injury
• Droughts starvation, thirst

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Catastrophes Public Health - 3

• There are many secondary health effects,
  depending on circumstances and human responses
• Crowding in shelters enhances disease
  transmission.
• Water contamination transmits microbes.
• Injuries from debris clearing.
• Mass relocation can lead to violence, starvation,
  disease transmission.

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Catastrophes Public Health - 4

• Health effects are accentuated by
• Loss of housing and sanitation
• Loss of food potable water
• Loss of health care facilities and personnel
• Loss of employment
• Loss of organized government support services.

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Catastrophes Public Health - 5

• Some determinants of health outcome
• Magnitude and extent of the event
• Pre-event health status
• Nutritional status
• Immunological experience/vaccines
• Educational level
• Preparedness and training of the public and
  health care workers (Bissell et al, 2004)

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Public Health Priorities

• Clean water and sanitation
• Safe and adequate food
• Shelter
• Epidemiologic surveillance/info
• Access to labs
• Access to pharmaceuticals
• Clinical personnel and facilities

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Infrastructure and Support Needed for Public
Health

• Water supply engineers and technicians.
• Clean bulk food, means of transporting it,
  personnel and equipment to prepare and distribute
  it.
• Adequate temporary shelter (not over-crowded or
  dirty) and shelter management personnel, as well
  as building supplies for people to repair their
  own shelters.
• Broad variety of temporary and permanent
  sanitation strategies, equipment and personnel.
  May need heavy equipment to create sewage systems.

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Infrastructure and Support Needed for Public
Health - 2

• Trained epidemiologic field personnel with
  assistants, computers, means of communication,
  transportation, mobile lab equipment, shelter.
• Means of conveying specimen samples to a
  qualified reference lab for diagnosis.
• Pharmaceutical supply and distribution network.
• Temporary or permanent hospitals, clinics,
  diagnostic and treatment equipment, all with
  power, water, sanitation and food.
• Clinicians of all levels, particularly those with
  primary care skills, and ancillary support staff.

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Role of Surge Capacity Planning in Catastrophes

• Given the overwhelming character of catastrophes,
  local surge capacity planning may be of little
  value. For catastrophes, the sense of surge
  capacity has to take on a national meaning, with
  the surge being taken up in clinical care
  facilities that may be geographically quite far
  away from the primary sites of the event.

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EM-Public Health Collaboration in Catastrophes

• Public health has scientific capability and, in
  some places, statutory responsibility, but
  virtually no logistics, transport, communications
  or law enforcement resources with which to
  conduct its work.
• Public health authorities have good experience
  coordinating within the health sector, but not
  with outside agencies.

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EM-Public Health Collaboration in Catastrophes - 2

• EM can conduct damage and needs assessments,
  except in the area of health, where EM will need
  the expertise and methods of public health.
• Public health workers and methods are needed to
  protect the health and productivity of EM
  personnel and responders.

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Public Health Section Exercise

• Group discussion Assume a major earthquake along
  the New Madrid Seismic Zone (NMSZ). There are
  gt100,000 injured. Hospitals and clinics are down,
  water and sewer systems are severed, road and
  bridge failures block food and medicine
  deliveries. What health concerns emerge from
  this scenario and how must EM and public health
  collaborate?