Module: Public Health Disaster Planning for Districts
Organization: East Africa HEALTH Alliance, 2009-2012
Author(s): Dr. Roy William Mayega (MakSPH) (Lead Author), Dr. Christoper
Orach-Garimoi (MakSPH), Dr. Simon Mamuya (Muhimbili Univ. SPH), Dr.
Joseph Chuwa (MoH, Tanzania), Dr. Tabu Simiyu (Moi Univ. SPH), Mr. Mike
Renny Wafula (OPM, Uganda), Dr. G. Kabagambe (LIPHEA)
Resource Title: Session 1.4: Vulnerability Analysis
License: Unless otherwise noted, this material is made available under the terms of the Creative
Commons Attribution 3.0 License: http://creativecommons.org/licenses/by/3.0/.
Disclaimer: Any medical information in this material is intended to inform and educate and is not a
tool for self-diagnosis or a replacement for medical evaluation, advice, diagnosis or treatment by
a healthcare professional. Please speak to your physician if you have questions about your
medical condition.
Remember the formula:
Disaster Risk = [Hazard X Vulnerability]/ [Capacity]
In the previous sessions, we looked at the first part of this equation i.e., the
Hazard Analysis. We saw that it has two multiplicative components:
1. The Probability of Occurrence of the disaster
2. The Potential Impact of the Disaster
However, the Disaster Risk Equation is incomplete if we do not consider
vulnerability. If a disaster occurs and it meets a very vulnerable community, the
effects of even a low hazard disaster are likely to be magnified.
In this session, we shall conduct a vulnerability analysis to complete this
PART A: Vulnerability Analysis: Vulnerability of Critical
The effects of a disaster are likely to be more magnified if the population or
infrastructure is more vulnerable. We therefore need to consider the vulnerability
1. Critical Infrastructure
2. The Population
In the first part of these exercises, we shall focus on determining a score for the
vulnerability of critical infrastructure in the district to the 3 top priority hazards that
you identified in the previous session.
1. Each team will examine the public health infrastructure in the district
2. Using the top three hazards (as identified in the previous exercise on
Hazard Analysis), each team will complete an infrastructure vulnerability
estimate for the critical infrastructure using Table One below
3. Use the following criteria:
0 = Not Vulnerable
1= Somewhat Vulnerable
2= Moderately Vulnerable
3= Very Vulnerable
Important Hint! Vulnerability of infrastructure should be viewed in a broad way.
In the simplest way, it could mean that buildings and roads are vulnerable. On
the other hand, it could mean that health units could be over-whelmed; drugs
may run out because of the disaster; in the case of some epidemics, health
workers (the human resources) may panic and run away from the health units,
resulting in a break down of service delivery. Therefore, each of the 3 priority
hazards should be studied carefully for the infrastructure items indicated
Table One: Vulnerability of Critical Infrastructure to the 3 Top Priority
Asset Vulnerability
Priority Hazard
Number 1
Priority Hazard
Number 2
Priority Hazard
Number 3
1. Building Structures
2. Electrical Power
3. Water Supply
4. Sanitation systems
5. Medical Equipment
6. Medical Supplies
7. Human Resources
8. Communications
9. Environmental Control
10. Roads
Sub-Total Score
Divide sub-total by 10;
Mean Infrastructure
Vulnerability Score:
Question: For which of the 3 Top Priority Hazards is your infrastructure most
Part B: Vulnerability Analysis: Vulnerability of the
Exercise: Using the three top hazards (as identified in the Hazard Analysis) each
team will complete a Population Vulnerability Estimate for the community using
table Two Below, according to the following criteria:
0 = Not Vulnerable
1= Somewhat Vulnerable
2= Moderately Vulnerable
3= Very Vulnerable
Hint: In order to score the items below, you need to ask your self two questions:
1. Do we have this situation in our district?
2. If yes, to what extent does this make us vulnerable to each of the 3 priority
1. Do we have food insecurity in this district? Yes
2. If Yes, to what extent does it make us vulnerable to the 3 top Hazards in this
Priority Hazard Number 1 (Epidemics): Score 1
Priority Hazard Number 2 (Drought): Score 3
Priority Hazard Number 3 (Fire): Score 0
Use Table Two below to score each of the 20 factors for the 3 priority hazards
After that, compute the mean population vulnerability score for the population
Table Two: Vulnerability of the Population to the 3 Top Priority Hazards
Population Vulnerability
Number 1
Number 2
Number 3
1. Poor people
2. Children and women
3. People with Disabilities
4. Lack of information
5. Lack of experience
6. Inadequate healthcare
7. Geographically isolated areas
8. Inadequate social organization
9. Malnourished people
10.Inappropriate development policies
11. Food insecurity
12. Societal stratification
13. Poor water and food quality
14. Limited district-level resources
15. Political perceptions
16. Graft/corruption
17. Lack of social order
18. High burden of illness
19. Inadequate disaster preparedness
20. Socio-cultural practices
Sub-Total Score
Divide sub-total by 20;
Mean Infrastructure Vulnerability
Part C: Summary of Vulnerability Scores
You have computed two types of mean vulnerability scores for the three top
priority hazards in your district: A mean vulnerability score for critical
infrastructure and one for the population. Now add these up for each of the
disasters and find the overall mean vulnerability score for both infrastructure and
the population. Use Table 3 for this computation.
Table 3: Summary of Vulnerability Ranking
Vulnerability Category
Mean Score
for Priority
Hazard 1
Mean Score
for Priority
Hazard 2
Mean Score
for Priority
Hazard 3
Infrastructure (C)
Population (D)
Average Vulnerability Score
(C+D)/2 = (E)
Question: Based on the total vulnerability scores for infrastructure and the
communities, to which of the 3 top priority hazards is your district more
vulnerable in case it occurred?
Part D: Completing the Disaster Risk Equation
Now transfer the Hazard Priority Score for each of the 3 priority hazards
that you computed in the previous session into the table below:
Insert the average vulnerability score (combining both infrastructure and
people) to the 3 priority hazards
The multiply them to obtain the Disaster Risk for the 3 priority hazards in
your district
Use Table Four below
Table Four: Product of Hazard and Vulnerability
Priority Score Vulnerability
Score (E)
(C X E)
Questions: Based on both Hazard and Vulnerability combined, does the ranking
of your top 3 priority hazards in your district change? If so, what is the new order
of importance of the 3 top hazards?
Conclusion of the Exercises
We have just completed the Equation:
Disaster Risk = [Hazard X Vulnerability]/[Capacity]
We have just conducted what we call the ‘Hazard Vulnerability Capacity
Analysis’ (HVCA) for our districts
It tell us:
1. The priority hazards to focus on and plan for in the districts
2. Whether vulnerability changes the effects of disasters
Extension Activity 1.4
Please refer to the additional notes attached for further information in the
implications of this analysis