Using Geographical Information System tool in containing influenza

pandemic threats

Republic of LebanonMinistry of Public Health

Epidemiological Surveillance ProgramNada 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

1918:

“Spanish Flu”

20-40 million deaths

A(H1N1)

1957:

“Asian Flu”

1-4 million deaths

A(H2N2)

1968:

“Hong Kong Flu”

1-4 million deaths

A(H3N2)

Credit: US National Museum of Health and Medicine

Next?

“XX Flu”

millions deaths

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 scale2. Can affect humans and cause severe disease3. But still can not be transmitted from human-

to-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

• 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

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

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 plan1. 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 plan1. 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 Recommendations1. Early detection, and rapid response

2. The main measures to prevent, control and eradicate HPAI are:

• 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

Source: FAO - 2005

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?– …

• 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?

– …

Lebanon: Influenza H7N7 risk Tyr caza, March-April 2006

How to avoid containment delay?

1. Be prepared2. Visualize risky areas3. Have centrally available

information and maps to decide on strategy and needed resources

4. Save time and act rapidly

Avian Influenza Preparednessusing GIS tool

1. Preparedness tool2. Visualization of risky areas3. Decision tool4. 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 exit2. Control (destroy) all poultry in the security zone (3km

radius)3. Detect poultry cases in a 7km radius zone with enhanced

veterinarian surveillance4. Detect human cases in affected areas5. Prepare health structures to manage human cases6. Close community gathering places7. Rise public and professional awareness

1. Quarantine - Security and Surveillance zones:

Actor Questions Parameters

Q1 MI/FSI What are the limits of the security and surveillance zones?

Q2 MI/FSI What are the needed resources to quarantine the security zone?

Needed quarantine resources / km (Human, equipment, financial, information)

Q3 MI/FSI What are the suitable places for the entry/exit check points?

Criteria for suitable places for check points

Q4 All What are the needed resources at the entry/exit check points?

Needed resources / check point (Human, equipment/material, financial, information)

1. Quarantine - Security and Surveillance zones:algorithm

Buffer 3km Buffered Zone 3km

Select Road-based

Security ZoneSecurity zone

IndexCase

Buffer 7km Buffered Zone7km

SelectRoads-based

Surveillance Zone

Roads

Surveillance zone

FSI Report:Needed

Quarantine resources

FSI Report:Suitable Entry/exit

check points

All Report:Needed

Resources at check points

Spatial map

Q1

Q1

Q2 Q3 Q4

Suitable places For checkpoints

Suitable check points

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

2. Destroy poultry in 3km radius zone: algorithm

FarmsDataBase

Select within Security Zone

Target Farms in security zone

MOA Report:Needed

stamping resources

MOA Report:Target

Farms in Security Zone

MOA Report:Compensation

estimations

Water resources

Land UseSuitability place

for burialSuitable Places

for carcasses burial

Spatial map

MOA Report:Needed

Disinfections resources

Security zone

Farms including slaughterhouses and poultry live markets

Q1

Q1

Q5

Q3Q2

Q4

Actor Questions Parameters

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?

Needed resources for active surveillance, specimens collection and transportation / surveillance point

3. Detect poultry cases in a 7km radius zone: questions

3. Detect poultry cases in a 7km radius zone: algorithm

FarmsDataBase

Proximity

Target Farms in surveillance zone

Select within Surveillance Zone

Target migratory Birds itinerary

MOA Report:Needed

surveillance resources

MOA Report:Target wild

birds surveillance

MOA Report:Target

Farms in Surveillance

zone

Migratory birds itinerary

Surveillance zone

Index Case

Farms including slaughterhouses and poultry live markets

Q3

Q2

Q1

Q1

Q2

Actor Questions ParametersQ1 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?

-Needed resources for active surveillance, health monitoring, specimens collection and transportation-Needed resources for antiviral prophylaxis

4. Detect human cases in affected area:

4. Detect human cases in affected area: algorithm

Population

ProximityMOH Report:

Target Households for active surveillance

Spatial Map(building blocks)

Health Structures

Surveillance zone

Security zone

Target Farms in security zone

MOH Report:Target Health Stru.

for active surveillance

Target poultry workers

Target households

Target Health structures for surveillance

MOH Report:Target Poultry workers for active surveillance

Q3

Q4

Q1

MOH Report:Needed

Surveillance resources

Q5

Q1

Q4

Q3

MOH Report:Needed

Anti-viral prophylaxisresources

Q5

Actor Questions Parameters

Q1 MOH What are targeted health structures for case referral?

Criteria for reference health structures

Q2 MOH What are targeted health structures for training on case management and infection control?

Criteria for training health structures

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:

5. Prepare health structures to manage human cases:algorithm

Population

Suitability & Proximity

MOH Report:Needed resources

for training on case management

and infection controlSpatial Map(building blocks)

Health Structures

Surveillance zone

Security zone

MOH Report:Reference

Health structures

Reference Health structures

MOH Report:Reference patient transport service

Q1Q1

Q1

Q3

Patient transport services

Reference Transport services

Q1

Target health structures

for training

Q2

MOH Report:Needed resources for

protecting care providers and antiviral prophylaxis

Q4

Actor QuestionsQ1 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:

6. Close community gathering places: algorithm

Target Schools for closure

Proximity

Target Common places for closure

Report:Target

Common places

Report:Needed resources

to ensure Closure

implementation

Report:Target

schools

Schools

Community gathering

places

Spatial Map(building blocks)

Surveillance zone

Security zone