1. Pathway Risk Analysis: NAPPO RSPM 31 (2012)
Presented to RPPO-TC
August, 2012

2. Definitions
Pathway: “any means that allows the entry or spread of a pest” (ISPM 5).
Pathway risk analysis: a process for evaluating the pest risk and risk management options associated with one or more pathways for the introduction or spread of pests.

3. Pathway RA may be used to…
Identify potential pathways for the introduction and spread of pests,
Assess the likelihood and consequences of the introduction or spread of pests along a pathway,
Compare and rank multiple pests and pathways according to their level of risk, and
Identify risk management options and evaluate their efficacy.

4. Pet trade: a difficult pathway to manage

5. Comparison with other risk analyses
Pest RA:
focuses on the risk associated with a particular pest moving along one or more pathways
Commodity RA:
are a special type of pathway risk analysis;
are a collection of individual pest risk analyses grouped together based on a single commodity

6. The pathway continuum model
Pathways represent a broad continuum, from pest association
with the pathway at the region of origin, through entry,
establishment, and finally to spread within the region at risk. Of
particular concern to risk assessors are the conditions and events
that occur along these pathways which either reduce or increase
pest risk.
Establishment
Spread
Introduction
Origin
Widely
Distributed
Events for introduction
Events for spread
Pest prevalence
Time
Inspection
Detection
Pathway Continuum Model

7. Examples of objectives of pathway risk analyses
Evaluate container loading practices at a packing facility to determine how they affect the likelihood of contaminating pests.
Calculate the probability of wood boring pests spreading from the transport of infested material to landfills.
Evaluate the most likely pathway by which a newly detected pest became established (e.g., traceback).
Estimate the change in the risk of pest introduction should one of the risk mitigation measures in a systems approach fail.
Identify the relative risk of a number of different commodity pathways, in order to prioritize inspection efforts at ports.

8. Types of pathway risk analysis
Passengers
Single pathway, single pest (e.g., marble tile transporting a snail species)
Multiple pathways, single pest (e.g., trade, tourism, and military equipment enabling the movement of a pest between regions)
Single pathway, multiple pests (e.g., commodity from one location with a number of associated pests)
Multiple pathways, multiple pests (e.g., air and sea cargo from another country carrying multiple pests).
Yemshanov et al., 2010

9. Additional characteristics
Diversity & variation:
Pathway risk analyses are highly variable.
Analyses are inherently unique due to differences in objectives, scope of analysis, data availability, and analytical approach.
They may stop at different stages.
Scope: May range from
specific and narrow (e.g., an imported fruit from a particular country)
to general and broad (e.g., wooden handicrafts from China – many types of articles with different pests)

10. Pathway RA stages (similar to PRA in ISPM 2 and 11)
Pathway description (Stage 2)
Information is gathered about the pathway(s) of concern,
Pathways are described and characterized:
Origin and destinations
Relevant events and conditions
Limits of the analysis
Assumptions, etc.
Conclusion of pathway description
Initiation phase (Stage 1)
Identification of the pathway and pests of concern
Identification of the area of analysis
Background information
Scope and objectives of the analysis
Conclusion of initiation

11. Pathway risk assessment (Stage 3)
Pathway categorization
Pathway mapping and modeling
Pests of concern
Assessment of pathway events related to the introduction and spread of pests
Consequences of pest introduction and spread
Pathway comparison
Conclusion of the pathway risk assessment

12. Pathway risk management (Stage 4)
Control points
Systems approach
Uncertainty in risk management
Natural dispersal and impact
Monitoring effectiveness
Conclusion of risk management
Natural dispersal

13. QUESTIONS?