1. Health Risk from Natural Disasters
Mollie Mahany, MPH
Senior Public Health Advisor
Centers for Disease Control and Prevention

2. Definition of a natural disaster
A disaster that is caused by naturally-occurring hazards
Natural disasters are defined as:
“Disasters that are caused by naturally-occurring hazards”
Naturally-occurring hazards include meteorological, geological and biological hazards
Examples of natural disasters include:
Tornadoes
Typhoons
floods
Storm surges
Windstorms
Wildfires
Heat waves
Dust storms
Snowstorms
Earthquakes
Tsunamis
Volcanic
Landslides
Avalanches
Outbreaks of infectious disease

3. Classes of natural disasters
Hydro-
meteorological
Floods
Storm surges
Windstorms
Wildfires
Heat waves
Dust storms
Snowstorms
Geological
Earthquakes
Tsunamis
Volcanic
Landslides
Avalanches
Biological
Epidemics
Pandemics
Disasters may also be classified according to the type of hazard that causes the disaster.
This is the most common type of classification, and the one that we will use for most of this course
There are three main hazard-based classifications for natural disasters. These are as follows:
hydro-meteorological – having to do with weather (i.e. floods, typhoons, heat waves, etc.)
geological – having to do with the earth, land and sea (i.e. earthquakes, volcanoes, tsunamis, landslides, etc)
biological – refers to infectious diseases (i.e. influenza, dengue fever, etc)

4. Hazard-based classification of natural disasters
Geological
Hydro-meteorological
Seismic
Volcanic
High
precipitation
Low precipitation
Earth-quake
Tsunami
Volcanic eruption
Land-slide
Tropical Cyclone
Flood
Drought
Wildfire
This table shows how 2 of the 3 hazard-based classification may be further sub-divided.
The 3 categories of natural disasters are caused by geological, hydro-meteorological and biological hazards
Geological disasters may be further sub-divided into seismic and volcanic hazards:
Seismic means having to do with earthquakes and the tsunamis that result from earthquakes.
Volcanic – disasters related to volcanic eruptions
Hydro-meteorological disasters maybe further subdivided into high precipitation and low precipitation events:
High precipitation events involve hazards that our associated with too much rain.
As you can see on the slide, landslides are geological events that have to do with the earth, but landslides are also in the high precipitation area because, in some cases, they are also caused by heavy rain.
For example, in 2002, heavy rains associated with Typhoon Chata’an caused landslides to occur in Chuuk, Micronesia killing 43 persons.
Low precipitation events involve hazards that are associated with too little rain.
Biological natural disasters may also be further subdivided.
These subdivisions include:
outbreaks;
epidemics; and
pandemics
Keim 2010

5. Pacific islanders carry the highest disaster burden in the world
Number of disasters reported:
(Incidence a measure of the frequency with which new events occur among a population during a specified period.  In the case of this graph, the incidence of natural disasters is being reported on an annual basis.)
The graph reveals that there has been a sharp increase in the number of natural disasters reported every year over the last 100 years.
It is not yet understood why the number of natural disasters has been steadily decreasing since 2000

6. Pacific islanders have the 2nd highest mortality rate in the world
Number of disasters reported:
(Incidence a measure of the frequency with which new events occur among a population during a specified period.  In the case of this graph, the incidence of natural disasters is being reported on an annual basis.)
The graph reveals that there has been a sharp increase in the number of natural disasters reported every year over the last 100 years.
It is not yet understood why the number of natural disasters has been steadily decreasing since 2000

7. Pacific islands have the 2nd highest per capita losses in the world
Number of disasters reported:
(Incidence a measure of the frequency with which new events occur among a population during a specified period.  In the case of this graph, the incidence of natural disasters is being reported on an annual basis.)
The graph reveals that there has been a sharp increase in the number of natural disasters reported every year over the last 100 years.
It is not yet understood why the number of natural disasters has been steadily decreasing since 2000

8. The incidence of natural disasters is increasing worldwide (1900-2005)
Natural disasters according to type:
Biological – infectious disease outbreaks (e.g. SARS, influenza) – the dark purple line
Geological – related to the earth (e.g. earthquakes, tsunamis) – a light purple line
Hydrometeorological – related to weather (e.g. typhoons, tornadoes)- the light blue line
As we can see in this graph, the incidence of hydro-meteorological (weather-related) disasters has increased remarkably since the 1960’s
It is not yet known why weather-related disasters have been increasing so much more in recent years, but it is thought to be related to climate change.

9. Top 4 causes of death due to disasters in the Pacific
Tsunamis
Cyclones
Floods
Landslides
During the last 4 decades, the world’s five worst natural disasters each killed well over 100,000 people
In many cases the deaths were over 200,000 – 300,000 people killed.
These numbers are deaths only, doesn’t include the number of people affected by these large events
Photo is of the Indian Ocean tsunami in 2004.
(source:

10. Most disaster deaths occur BEFORE emergency response
Hazard
Cause of death
Tsunami
Severe trauma and drowning
Cyclones
Drowning
Floods
Landslides
Severe trauma

11. Vulnerability to natural disasters
95% of natural disaster deaths occur among 66% of the poorest countries
The Pacific is one of the most disaster prone area in the world followed by Asia; Latin America and Africa; and North America, Europe, and Australia, the least.
Reasons why disaster deaths occur more frequently in developing countries among the poor:
Housing: Poor are least able to afford housing that can withstand natural disasters such as earthquakes and hurricanes; they often live along the coast in developing countries where hurricanes, storm surge, or tsunamis may affect them; or in flood planes; on unstable slopes that are susceptible to landslides; or next to hazardous industrial sites.
Education: poor generally aren’t as educated in preparedness behaviors or actions they can take in disasters to save their lives.
Building codes: Generally, in developing countries building codes are either not present or not as strict and not enforced if present and therefore are less likely to withstand earthquakes and hurricane
Disaster warnings and alerts as well as evacuation plans are not as well developed as in industrialized countries.
Disaster planning and education of the public generally not as developed as in industrial countries. Developing countries have the less resources for emergency medical response and less highly trained responders.
Developing countries have fewer resources and have decreased capacity to respond and recover from disasters.

12. Public health consequences of natural disasters
Death
Injuries
Loss of clean water
Loss of shelter
Loss of personal household goods
Major population movements
Loss of sanitation
Loss of routine hygiene
Disruption of solid waste management
Public concern for safety
Increased pests & vectors
Damage to health care system
Worsening of chronic illnesses
Loss of electricity
Toxic/ hazardous exposure
Loss of food supply
There are 16 categories of public health consequences related to all natural disasters.
Despite the fact that there are many different types of natural disasters, all may have these consequences that can be grouped into 16 categories
Differences between the different natural disasters a related to the degree that one public health consequences may be increased as compared to another.
For example, during typhoons , there are usually relatively few deaths. However, there is a large area , which commonly loses shelter and clean water.
In comparison, during landslides there are usually more deaths than typhoons, but less loss of shelter and clean water.
So in both cases we should be planning for the public health consequences of: deaths, loss of clean water, and loss of shelter, regardless of the cause.
By preparing for each of these 16 categories we can be prepared for all natural disasters.
Although we classify the list as public health consequences – “having an impact on the health of the public” – it should be noted that during a disaster response, many agencies beyond public health are required to assist the public.
It is not just a problem to be handled by public health professionals alone.
Example: Getting soap and clean water to a shelter could involve a variety of government and private agencies. Public health probably does not have large quantities of soap and water so they would require help from other agencies to provide these items to those who need them. This is true for many other consequences, such as loss of electricity, etc.

13. Earthquakes and tsunamis often cause many severe injuries.
Consequence
Earthquake
Tsunami
Volcanic eruption
Landslide
Tropical Cyclone
Flood
Drought
Wildfire
Deaths
Many
Few to moderate
Few, but many in poor nations
Few
Severe injuries
Unlikely
Loss of clean water
Focal to widespread
Focal
Widespread
Loss of shelter
Loss of personal / household goods
Major population movements
Loss of routine hygiene
Loss of sanitation
Disruption of solid waste mgt
Public concern for safety
High
Moderate to High
Low to moderate
Increased pests
Loss or damage of health care system
Worsening of chronic illnesses
Loss of electrical power
Toxic exposures
Few to moderate for CO poisoning
Widespread for air, soil and surface water
Widespread for air
Food scarcity
Common in low-lying coastal areas
Widespread in poor nations
This is a table showing the public health consequences common to all natural disasters.
Almost all of the consequences will (or may) happen for almost every hazard
The impact (degree or severity of the consequence) will vary depending on the type and size of the event.
Examples –
Earthquakes and tsunamis often cause many severe injuries.
Volcanoes and landslides commonly cause a few or a moderate number of severe injuries.
Cyclones, floods and wildfires often cause fewer injuries.
It is unlikely that drought will cause any severe injuries at all.

14. So, how do we reduce health risk?
Reduce exposures
Identify the hazard
Monitor the hazard
Provide early warning
Evacuate people at risk
Reduce vulnerability
Promote health and education
Strengthen public health and healthcare
Protect key resources
Livelihoods, shelter, food, water, sanitation

15. Thank you