Transcript Infectious Diseases and Natural Disasters

Infectious Diseases
and
Natural Disasters
Background
 Historically, infectious disease epidemics have
high mortality
 Disasters have potential for social disruption
and death
 Epidemics compounded when infrastructure
breaks down
 Can a natural disaster lead to an epidemic of
an infectious disease?
 Are there emerging infectious diseases after a
natural disaster?
What is an emerging
infectious disease?
 In 1991, Institute of Medicine attempted
to define:
 – “new, re-emerging, or drug resistant
infections whose incidence in humans
has increased within the past 2 decades
or whose incidence threatens to increase
in the near future.”
Phases of Disaster
 Impact Phase (0-4 days)
– Extrication
– Immediate soft tissue infections
 Post impact Phase (4 days- 4 weeks)
– Airborne, foodborne, waterborne and vector
diseases
 Recovery phase (after 4 weeks)
– Those with long incubation and of chronic
disease, vectorborne
Factors for Disease
Transmission After a
Disaster
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Environmental considerations
Endemic organisms
Population characteristics
Pre- event structure and public health
Type and magnitude of the disaster
Environmental Considerations
 Climate
– Cold- airborne
– Warm- waterborne
 Season (USA)
– Winter- influenza
– Summer- enterovirus
 Rainfall
– El Nino years increase malaria
– Drought-malnutrition-disease
 Geography
– Isolation from resources
Endemic organisms
(exclusively native to a place)
 Infectious organisms endemic to a region will
be present after the disaster
 Agents not endemic before the event are
UNLIKELY to be present after
 Rare disease may be more common
 Unlikely a new or changed disease will occur
 Deliberate introduction could change this factor
Population Characteristics
 Density
– Displaced populations
– Refugee camps
 Age
– Increased elderly or children
 Chronic Disease
– Malnutrition
– Heart disease
– Transplantation
Population Characteristics
 Education
– Less responsive to disaster teams
 Religion
 Hygiene
– Underlying health education of public
 Trauma
– Penetrating, blunt, burns
 Stress
Pre-event resources
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Sanitation
Primary health care and nutrition
Disaster preparedness
Disease surveillance
Equipment and medications
Transportation
Roads
Medical infrastructure
Type of disaster
 Earthquake
– Crush and penetrating injuries
 Hurricane (Monsoon, Typhoon) and Flooding
– Water contamination, vector borne diseases
 Tornado
– Crush
 Volcano
 – Water contamination, airway diseases
 Magnitude
– Bigger can mean more likelihood for
epidemics
Dominican Republic, 1979
 Hurricane David and Fredrick on Aug 31 and
Sept 5th 1979
 >2,300 dead immediately
 Marked increase in all diseases measured
6 months after the hurricane
– Thyphoid fever
– Gastroenteritis
– Measles
– Viral hepatitis
Epidemics after Disasters
San Francisco, 1907 Fires; Plague
resulting from Quarantine failure
Duluth, MN, 1918 Forest Fire; Influenza
resulting from crowding and epidemic
Italy, 1976 Earthquake; Salmonella Carriers
due to sanitation stoppage
Summary of Factors
 Many factors play a role in disease
development and outbreaks
 Change of disease not likely to play role
– Increase in rare diseases
 Change and/or closing of public health
measures play a big role
What infections would we
see today?
 Endemic organisms
 Post-impact phase
 Recovery Phase
Post-Impact Phase Infections
 Crush and penetrating trauma
– Skin and soft tissue disruption (MRSA)
– Muscle/tissue necrosis
– Toxin production disease
– Burns
 Waterborne
– Gastroenteritis
– Cholera
– Non-cholera dysentery
– Hepatitis
– Rare diseases
Post-Impact Phase Infections
 Vector borne
– Malaria
– WNV, other viral encephalitis
– Dengue and Yellow fever
– Typhus
 Respiratory
– Viral
– CAP
– Rare disease
 Other
– Blood transfusions
Recovery Phase Infections
 These agents need a longer incubation
period
– TB
– Schistosomiasis
– Lieshmaniasis
– Leptospirosis
– Nosocomial infections of chronic
disease
General disaster reminders
 Vaccinations are the mainstay of
outbreak control in many situations
 Dead bodies pose little to no infectious
disease risk; however this is debated
 Early surveillance and hygiene can
prevent outbreaks
Conclusions
 Infectious diseases may play a role in the
post disaster period
 These diseases will vary depending on
many factors
 If the disease is not present before the
disaster, unlikely to be there after
Conclusions
 Early recognition of certain diseases in
disaster setting important
 Halting infrastructure and response has
led to most increases in infectious
diseases
 know where you are going and what is
endemic