Spatial analysis to identify risk areas
of an important animal disease
(Highly Pathogenic Avian Influenza)
and to evaluate current strategy
in health surveillance in Europe
Irene Iglesias [email protected] MartínezAna de la TorreMª Jesús MuñozJM Sánchez-Vizcaíno
(CISA-INIA UCM)
Animal diseases control
Affected animals and.....:
Trade in animal products
Vaccines
Control of disease: loss of livestock, compensation, health costs
Public confidence
......
Animal diseases control
Zoonotics
Tuberculosis
Salmonella
Avian Influenza
…
Animal diseases control
Affected countries: stop spread
Free countries: early detection
Preventivesurveillance
Animal diseases control: SURVEILLANCE
random samplingsystem
Preventivesurveillance
Animal diseases control: SURVEILLANCE
massive expansionavian influenza
TARGETTARGET
SURVEILLANCESURVEILLANCE
RiskRiskassessmentassessment
random samplingsystem
assessmentassessment
EC 2010/367/EU
Preventivesurveillance
Animal diseases control: SURVEILLANCE
TARGETTARGET
SURVEILLANCESURVEILLANCE
RiskRiskassessmentassessmentassessmentassessment
Spatial analysis:
Exploring data
Risk assessment
Modelling diseases
G.I.S.
Preventivesurveillance
• Affected countries (2004-2010)
HighlyPathogenicAvianInfluenza
( SubtypeH5N1)
has killed ≈ 400 million domestic birds
Cbc.caartsandopinion.com new.dpi.vic.gov.auartsandopinion.com new.dpi.vic.gov.au
Social alarm :332 fatal human cases
High economic losses ≈ ($20 billion)
HighlyPathogenicAvianInfluenza
( SubtypeH5N1)
The main difference...
• has killed ≈ 400 million domestic birds
Natural reservoir����Affected birds
Has killed ≈ 15.000 waterbirds
Highly Pathogenic Avian Influenza
( Subtype H5N1)
In the last 4 years...
HighlyPathogenicAvianInfluenza
( SubtypeH5N1)
•Tradepoultry
•MigrationrouteswaterbirdsSpread in Europe
Spatial analysis to identify risk areas of Highly Pathogenic Avian Influenza and to evaluate current strategy of
health surveillance in Europehealth surveillance in Europe
Visualization
Spatial analysis process: Modelling
Data base
Exploration
Modelling
StatisticsUseful & efficient decision-
making tool for different
epidemiological situations
in animal health
Data base
Avian InfluenzaCases in domestic birds
Avian InfluenzaCases in wildbirds Modelling with G.I.S.
Domestic birdsCensus/farms/location
WildbirdsCensus/location
Cases in domestic birds Cases in wildbirds Modelling with G.I.S.
WHERE should we do an efficient surveillance of
Avian Influenza in wildbirds???
TARGETTARGET
SURVEILLANCESURVEILLANCESURVEILLANCESURVEILLANCE
Spatial analysis to identify risk areas of Highly Pathogenic Avian Influenzaof Highly Pathogenic Avian Influenza
in waterbirds
1. Infected water represents a recognized mechanism for the virus transmission
within waterbird populations
2. Wetlands concentrate many waterbirds species → Increasing the risk of infection
Importance of wetlands in spread of Avian _Influenza
Modelizationof ENVIRONMENTAL RISK FACTOR for European WETLANDS
Distances Ramsar European Wetlands (Wetlands.org)
Avian influenza cases in wild birds (06-09)
Infected wetlands!
“Positive wetland”Wildbirds outbreaks
( Ramsar wetland
Europe
WetlandsOutbreaksInfected wetlands
16Km
• Analysis tools• Spatial analysis
Study wetlands characteristics
Modelizationof ENVIRONMENTAL RISK FACTOR for European WETLANDS
Water: Salinity, permanence
organic or mineral soil, ....
Land Use: Forestry, hunting,
Agriculture, aquaculture,...
Biological: Wintering birds area,
species, important area for fish..Logistic regression
analysis
• Analysis tools• Spatial analysis
• Logistic regressionIdentification of risk factors
•Mixosaline water
•Forestry around wetland
•Wintering waterbird area
analysis
!
“Infected wetlands”
Waterbird cases
( Ramsar wetland
Europa
Risk map for ocurrence of Avian Influenza in wildbirds
Logistic regression model
2009GERMANY
ROMANIA 2010
BULGARIA 2010
• Spatial analysis:Kernel
USEFULINFORMATION
ON TARGET SURVEILLANCE
Aplication of the model a national level: Spain
Increased Nº wetlands
•Wetlands Ramsar+Spanish Wetlands
(NationalDatabase)
Interpolate data model : IDW
(Inverse Distance Weighting)Provinces
Risk of modelHigh: 0.83
Logistic regression model
Adjust risk by climatic data
( temperature analysis)
• Geostatistical analysis:IDW
Low:0.10
Survival curve
Survival by temperature analysis
Wildbird case in Pais Vasco (2006)
Salburua
MCDMulticriteria
Decision:
Logistic regression model
Wildbird case in Pais Vasco (2006)
Farm affected
contact with wildbirds
(2009)
Almoguera
• Spatial analysis:Math
HighHigh
LowLow
RiskRisk valuesvalues ((OctoberOctober))
ProvincesProvinces
EuropeEurope
Risk of ocurrence of Avian Influenza in wildbirds
2006 High Surveillance AreasOf the National surveillance Plan(Ministery Agriculture and Food)
MCDMulticriteria
Decision:
Logistic regression model
USEFULINFORMATION ����IMPROVE
SURVEILLANCE PLANS
HighHigh
LowLow
RiskRisk valuesvalues ((OctoberOctober))
ProvincesProvinces
EuropeEurope
Risk of ocurrence of Avian Influenza in wildbirds
Spatial analysis to EVALUATE currentstrategy in health surveillance in Europe.
Co-kriging
Probability of ocurrence of Avian Influenza
Test pointsAvian Influenza cases
+ co-variableWetlands (>20.000 Waterbirds)
+ co-variantePoultry density
• Geostatistical analysis:Co-kriging
Co-kriging
Probability of ocurrence of Avian Influenza
• Geostatistical analysis:Co-kriging
Co-kriging
Probability of ocurrence of Avian Influenza
NLNL
DEDE
USEFULINFORMATION ����EVALUATE
SURVEILLANCESTRATEGIES
• Geostatistical analysis:Co-kriging
SPSP
Sampling> Risk Avian Influenza
Sampling< Risk Avian Influenza
• Grubb’s test, P<0.01
• Spearman’s coefficient
$
$
Veterinary Authorities and
Organisations
Identify HOT SPOT of RISK� Adequate control mesures
Help to take decisions for� TARGET SURVEILLANCE (According to EC
recommendations)
Spatial Analysis is an essential tool for Animal Health
CONCLUSIONS
Reduce health costs and improve efficiency
of veterinary intervention
Increase INFORMATION about dynamic of diseases � improve
PREVENTION & CONTROL PLANS� Prevent or reduce consequences
EVALUATE control and prevention strategies
Laguna de Pitillas (Navarra) http://www.navarra.es/home_es/Actualidad/Informes
Financial support: CC08-020, FAU2008-00001-C02-01