Document 7236608
Download
Report
Transcript Document 7236608
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
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
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