Using Geographical Information
System tool in containing influenza
pandemic threats
Republic of Lebanon
Ministry of Public Health
Epidemiological Surveillance Program
Nada Ghosn, MD
Influenza:
seasonal, pandemic, avian
Human influenza
• Seasonal influenza:
– Annual outbreaks due to minor changes in the
surface of the influenza viruses
– Human have partial immunity due to previous
infections.
• Pandemic influenza: )‫(الجائحة‬
– Global and worldwide severe epidemic
– Due to major change
– No human have partial of fully immunity
against infection because it is a completely new
virus.
Latest Influenza pandemics
Credit: US National Museum of Health
and Medicine
1918:
1957:
1968:
Next?
“Spanish Flu”
“Asian Flu”
“Hong Kong Flu”
“XX Flu”
20-40 million deaths
1-4 million deaths
1-4 million deaths
millions deaths
A(H1N1)
A(H2N2)
A(H3N2)
A(H5N1)?
Animal influenza
• Avian influenza
– Highly Pathogenic Avian Influenza (HPAI)
– Low Pathogenic Avian Influenza
• Outbreaks of new avian influenza
– Increase the risk of a human pandemic
– Through the merging of animal and human
influenza viruses.
Influenza virus H5N1
•
The new H5N1 avian influenza is a
potential candidate for pandemic
influenza:
1. Can affect animals and birds on a large scale
2. Can affect humans and cause severe disease
3. But still can not be transmitted from humanto-human
How to control/prevent pandemic
influenza?
1. Containment of potential human
pandemics at the source
2. Containment of HPAI in animals
at the source
Pandemic Influenza modeling:
Time factor
Any delay will reduce the
probability of eliminating large
epidemics in humans
Probability of eliminating a large epidemic using social and geographical targeting
prophylaxis, varying with the delay (0-4 days) from case detection to prophylaxis for
the 5-km radius policy
• Delay of 4 days reduce
the probability of
eliminating a large
epidemic of a new
pandemic virus to:
– <50% for a virus with
R0=>1.5
– R0 quantifies the
transmissibility of
pathogen
Source: Ferguson, Derek, Cummings, Cauchemaz, Fraser, Riley, Meeyai, Lamsiiriithaworn, Burke. Strategies for containing an emerging
influenza pandemic in Southeast Asia. Nature. Vol. 437. 8 September 2005
Containment pandemic influenza
WHO plan:
time factor
The success of any strategy for
containing an emerging pandemic
virus is strictly TIME DEPENDENT
WHO pandemic influenza plan
1. The success of any strategy for containing an
emerging pandemic virus is strictly TIME
DEPENDENT.
2. Objectives of containment strategy
– To stop, or at least to slow, the spread of pandemic
influenza at the source of its emergence in order to
reduce global morbidity and mortality
Source: WHO pandemic influenza draft protocol for rapid response and containment. 30 May 2006
WHO pandemic influenza plan
1. Recognition of the event:
–
–
Epidemiological and virological signals
Steps of initial investigation
2. Verifying the event:
–
–
Risk assessment
Immediate control measures
3. Containing the event:
–
–
–
Decision to launch a containment operation
Phase 1 - standard measures to reduce transmission: case
management, infection control, antiviral treatment,
intensified surveillance, contact tracing, monitoring contacts
for signs of illness
Phase 2 - exceptional measures: voluntary quarantine, social
distancing, mass antiviral prophylaxis
Source: WHO pandemic influenza draft protocol for rapid response and containment. 30 May 2006
Containment avian influenza FAO plan:
Time factor
Timely reporting and timely
response
FAO Recommendations
1. Early detection, and rapid response
2. The main measures to prevent, control and eradicate
HPAI are:
•
•
•
•
•
•
•
Source: FAO - 2005
Effective disease surveillance for early detection and reporting
Enhanced biosecurity of poultry farms
Control of movement of birds and products
Changes to industry practices to reduce risk
Rapid, humane destruction of infected poultry and poultry at high
risk of infection (stamping out)
Disposal of carcasses and potentially infective material in a
biosecure and environmentally manner
Proper use of vaccine
Containment factors: available
information
Available information can reduce
delay in conducting response
measures
Lebanon,
March-April 2006
Influenza H7N7 risk
Tyr caza
Lebanon: Influenza H7N7 risk
Tyr caza, March-April 2006
• MOA:
– What is the area size?
– What are the target farms?
– What are the target birds
size?
– …
• Collecting data was time
consuming (>2 days) and
has delayed the stamping
out measures
Lebanon: Influenza H7N7 risk
Tyr caza, March-April 2006
• MOI
– What is the target area?
– What is the area
targeted for quarantine?
– What is the perimeter?
– How many human
resources are needed?
– …
Lebanon: Influenza H7N7 risk
Tyr caza, March-April 2006
• Municipality:
– How many human
resources are needed?
– …
• Short cut of human
resources was
observed and
prolonged field
activities
Lebanon: Influenza H7N7 risk
Tyr caza, March-April 2006
• MOPH:
– What are the exposed
persons targeted for health
monitoring ad active
surveillance? Professionals,
farms, households…
– What are the health
structures in place for case
referral and case
management?
– What are the needed
resources?
– …
How to avoid containment delay?
1. Be prepared
2. Visualize risky areas
3. Have centrally available
information and maps to decide
on strategy and needed resources
4. Save time and act rapidly
Avian Influenza Preparedness
using GIS tool
1.
2.
3.
4.
Preparedness tool
Visualization of risky areas
Decision tool
Save time
If Influenza A/H5N1 virus
appears in Lebanon
• All response measures aim to:
– Prevent the spread of the virus
– Contain the virus at the source (focus)
If Influenza A/H5N1 virus
appears in Lebanon
•
Response measures include:
1. Specify a 3km radius zone from the index case and
control its movements at entry and exit
2. Control (destroy) all poultry in the security zone (3km
radius)
3. Detect poultry cases in a 7km radius zone with enhanced
veterinarian surveillance
4. Detect human cases in affected areas
5. Prepare health structures to manage human cases
6. Close community gathering places
7. Rise public and professional awareness
1.
Quarantine - Security and Surveillance zones:
Actor
Q1
MI/FSI
Q2
MI/FSI
Q3
MI/FSI
Q4
All
Questions
What are the limits of the
security and surveillance
zones?
What are the needed
resources to quarantine the
security zone?
What are the suitable
places for the entry/exit
check points?
What are the needed
resources at the entry/exit
check points?
Parameters
Needed quarantine resources /
km (Human, equipment, financial,
information)
Criteria for suitable places for
check points
Needed resources / check
point (Human, equipment/material,
financial, information)
1.
Quarantine - Security and Surveillance zones:
algorithm
Roads
Spatial map
Buffer 3km
Buffered Zone
3km
Select
Road-based
Security Zone
Buffer 7km
Buffered Zone
7km
Select
Roads-based
Surveillance Zone
Q1
Security zone
Surveillance
zone
Suitable places
For checkpoints
Suitable
check points
IndexCase
Q1
Q2
FSI Report:
Needed
Quarantine
resources
Q3
FSI Report:
Suitable
Entry/exit
check points
Q4
All
Report:
Needed
Resources at
check points
2. Destroy poultry in 3km radius zone
Actor
Questions
Parameters
Q1
MOA
What are target farms and
backyards for poultry stamping
out? What are the target poultry
population for stamping out?
Q2
MOA
What are the needed resources for
rapid and adequate stamping out?
Needed resources for adequate
stamping out ( backyard, traditional
& modern farm)
Q3
MOA
What are the needed resources for
farms disinfections?
Needed farms disinfections resources
Q4
MOA
What are the suitable places for
disposal carcasses and infective
material without water
contamination?
Criteria for suitable places for
carcasses burial without water
contamination
Q5
MOA/
MF
What are the needed resources for
farms compensation?
Compensation / poultry species, type
and age
2. Destroy poultry in 3km radius zone:
algorithm
Q1
MOA Report:
Target
Farms in
Security Zone
Security zone
Q5
Q1
FarmsDataBase
Select within
Security Zone
Target Farms
in security zone
MOA Report:
Compensation
estimations
Water resources
Land Use
Suitability place
for burial
Spatial map
Farms including slaughterhouses and poultry live markets
Q4
Suitable Places
for carcasses burial
Q2
Q3
MOA Report:
Needed
stamping
resources
MOA Report:
Needed
Disinfections
resources
3. Detect poultry cases in a 7km radius zone:
questions
Actor
Questions
Q1 MOA
What are the targeted farms
and backyards for active
surveillance?
Q2 MOA
What are the targeted wild
birds itinerary for active
surveillance?
Q3 MOA
What the needed resources
for active surveillance,
specimens collection and
transportation?
Parameters
Needed resources for active
surveillance, specimens collection
and transportation / surveillance point
3. Detect poultry cases in a 7km radius zone:
algorithm
Q1
MOA Report:
Target
Farms in
Surveillance
zone
FarmsDataBase
Q1
Select within
Surveillance Zone
Target Farms
in surveillance zone
Surveillance zone
Q2
Proximity
Target migratory
Birds itinerary
Migratory birds
itinerary
Q2
MOA Report:
Target wild
birds
surveillance
Q3
MOA Report:
Needed
surveillance
resources
Index Case
Farms including slaughterhouses and poultry live markets
4. Detect human cases in affected area:
Actor
Questions
Q1
MOH
What are targeted HEALTH
STRUCTURES for enhanced
and active surveillance?
Q3
MOH
What are targeted FARMS for
active human surveillance?
Q4
MOH
What are targeted
HOUSEHOLDS for active
human surveillance?
Q5
MOH
What the needed resources for
active surveillance, specimens
collection and transportation?
Parameters
-Needed resources for active
surveillance, health monitoring,
specimens collection and
transportation
-Needed resources for antiviral
prophylaxis
4. Detect human cases in affected area:
algorithm
Q1
Target
Health structures
for surveillance
Security zone
MOH Report:Q1
Target Health Stru.
for active surveillance
Surveillance zone
Target
poultry workers
Health
Structures
Target Farms
in security zone
Proximity
MOH Report:
Target Poultry workers
for active surveillance
Q3
Q3
Target
households Q4
MOH Report:
Target HouseholdsQ4
for active surveillance
Spatial Map
(building blocks)
Q5
Population
MOH Report:
Needed
Surveillance
resources
MOH Report: Q5
Needed
Anti-viral prophylaxis
resources
5. Prepare health structures to manage human cases:
Actor
Questions
Parameters
Q1
MOH
What are targeted health structures Criteria for reference health
structures
for case referral?
Q2
MOH
What are targeted health structures Criteria for training health
structures
for training on case management
and infection control?
Q3
MOH
What are needed resources for
training on cases management and
infection control?
Needed resources for
training on cases
management and infection
control / site
Q4
MOH
What are needed resources for
protecting, monitoring and ensure
prophylaxis for care providers?
Needed resources for
protecting, monitoring and
ensure prophylaxis / person
5. Prepare health structures to manage human cases:
algorithm
Q1
Health
Structures
Reference Q1
Health structures
MOH Report:
Reference
Health structures
Patient transport
services
Q1
Q1
Reference
Transport services
Security zone
Surveillance zone
Q3
Suitability & Proximity
Q2
Spatial Map
(building blocks)
Population
MOH Report:
Reference patient
transport service
Target
health structures
for training
MOH Report:
Needed resources
for training on
case management
and infection control
Q4
MOH Report:
Needed resources for
protecting care providers
and antiviral prophylaxis
6. Close community gathering places:
Actor
Questions
Q1
All
What are targeted community gathering places for
closure?
Q2
All
What are needed resources to ensure closure of
targeted community gathering places?
6. Close community gathering places:
algorithm
Security zone
Target Schools
for closure
Report:
Target
schools
Target Common
places for closure
Report:
Target
Common
places
Surveillance zone
Spatial Map
(building blocks)
Proximity
Schools
Community
gathering
places
Report:
Needed resources
to ensure
Closure
implementation