A new semi-quantitative model to determine pest introduction

A new semi-quantitative model to determine pest introduction frequency Presented by: Simone Tuten on behalf of the Department of Agriculture, Western Australia Plant Biosecurity Team. International Plant Health Risk Analysis Workshop Niagara Falls, October 2005

Please note: The research reported here is in progress and is not finalised. The study results have not been subjected to scientific peer review and are presented purely as a demonstration of the authors’ current thinking. This presentation reflects the authors’ opinions and does not necessarily reflect the opinions of the Department of Agriculture, Western Australia. Additionally this research has been undertaken by the Western Australian State Department of Agriculture and not by National Government Departments. Any reliance on the information presented here is entirely at your own risk and the Department of Agriculture, Western Australia takes no responsibility whatsoever for the results of your doing so.

Background Western Australia

Background • Deserts

Background • Deserts • Limited road access

Background • Deserts • Limited road access • check points • 20 points

Background • Deserts • Limited road access • check points • Ports

Background • Pest and disease freedoms • Codling moth (Cydia pomonella ) • Oriental fruit moth (Grapholita molesta) • Apple scab (Venturia inaequali)

Background – Australia’s quarantine system Quarantine continuum • Partnership • States/Territories • Interstate trade • National • International trade

Background – Australia’s quarantine system Memorandum of Understanding • Agreement • Enables SPS compliance • Consistency

Background – WA Plant Biosecurity • State pest risk analyses • Market access • National pest risk analyses

Background – WA Plant Biosecurity Important considerations • integration of consequences and PEES • impact of volume • multiple pathways

The Model - Features • Enhances existing methodology • Incorporates • variable input data • trade volume • complex scenarios • multiple pathways • Pest initiated is best

The Model - Pathway Simplistic schematic Pest Present in Source Orchard No = 1 - Imp 1 Proportion of Fruit Purchased by Retailers Yes = Imp 1 Harvested Fruit Infected No = 1 – Imp 2 Proportion Purchased by Consumers from Retailers P 3 Proportion of Fruit Discarded as Waste Yes = Imp 2 P 4 Pest Viability Pest Survives Pack House Importation No = 1 – Imp 3 Viable Waste from Consumers Yes = Imp 3 Pest Survives Transport No = 1 – Imp 4 Yes = Imp 4 Pest Survives Quarantine Clearance Yes = Imp 5 Importation of Pest No = 1 – Imp 5 Distribution Exp 1 - Exp 2 - Exp 3 - Exposure o f Commercial Hosts Exposure o f Household Hosts Exposure o f Wild Hosts PPDc Partial Probability of Distribution to Commercial Hosts PPDh Partial Probability of Distribution to Household Hosts PPDw Partial Probability of Distribution to Wild Hosts Partial Probability of Establishment

The Model – Output Years before 1 st introduction = 1+Risk. Geomet(PEEannual)

1+Risk. Geomet(PEEannual)

The Model – Output Introduction frequency = 1/PEEannual

1/PEEannual

Volume and risk

Volume and risk • Non linear • high unit risk rapid increase at low volumes • low unit risk rapid increase occurs later • Consider all pathways and total volume • Monitor phytosanitary measures efficacy

Introduction frequency - applications Risk Communication • Tangible ALOP • Defining Consequences • integrating consequences with PEES • how often is too often?

Introduction frequency - applications Management strategies • phytosanitary measures efficacy Non-SPS application • development of policy • business planning • strategy planning to minimise impact of trade

Where to from here? Validation • Check model assumptions • using data collected during 2 seasons • review and release model Risk assessment • Link between introduction frequency and • consequences • ALOP

The plant biosecurity team Director Plant Biosecurity – Dr Shashi Sharma ssharma@agric. wa. gov. au Activity Specialist/Policy – Mr Mark Stuart mstuart@agric. wa. gov. au Pathologist/modelling – Ms Nichole Burges nburges@agric. wa. gov. au Pathologist – Dr Satendra Kumar skumar@agric. wa. gov. au Entomology/climate modelling – Mr Marc Poole mpoole@agric. wa. gov. au Entomology – Dr John Botha jbotha@agric. wa. gov. au Biometrics – Ms Jane Speijers jspeijers@agric. wa. gov. au Policy – Ms Simone Tuten stuten@agric. wa. gov. au