PRA procedures in the UK and in Europe

By Dr Ray CannonThe Food and Environment Research Agency (Fera)The Food and Environment Research Agency (Fera)

Thursday 28th July 2011, Bangkok

Format of the talk

• What is PRA? And Why is PRA done• Pathway, Pest or Policy-initiated? • Two PRA schemes:• Two PRA schemes:

– PART 1: The UK PRA scheme

• The EC PH Directive and Annex-listed quarantine pests for Europe– PART 2: EPPO PRA scheme

What is Pest Risk Analysis?

• The process of evaluating biological or other scientific and economic evidence to determine whether a pest should be regulated and the strength of any phytosanitary measures to be strength of any phytosanitary measures to be taken against it.

• Glossary of phytosanitary terms, ISPM No. 5

Pest Risk Analysis (PRA)

A structured, science-based process for evaluating:– Scientific and economic evidence– Determining whether the risk posed by an – Determining whether the risk posed by an

organism is sufficient to warrant phytosanitary regulation

– The nature and strength of the measures to take against it (PRM).

Why is PRA done?

• To evaluate and manage risks from specific pests and internationally traded commodities – To identify and assess risks to agricultural and

horticultural crops, forestry and the environment from plant pests plant pests

– To create lists of regulated pests– To produce lists of prohibited plants and plant

products– To assist in identifying appropriate management

options (including measures and treatments)

PRA schemes

• A framework for conducting analyses• Ensuring that all factors are taken into

account in detailed assessments• Highlighting those factors of key • Highlighting those factors of key

importance when there is time for only a brief appraisal, e.g. when pests are detected in perishable imports

EPPO (2002). Pest risk analysis on detection of a pest in an importedconsignment. EPPO Bulletin 32: 235-239.

PART 1.

• The UK Fera’s PRA scheme for specific pests and diseases

• With some examples of different pathway related PRAsrelated PRAs

• The three P’s!– Pathway, Pest or Policy

UK PRA System

INITIATION • Identity of pest• Reason for PRA• Define PRA areaRISK ASSESSMENT

• Capable of introduction ? (entry & establishment)

• Potential to cause damage ?RISK ASSESSMENT

• Present in UK/EU ?• EU/EPPO Pest Lists ?• Host Plants• Geographical Distribution

RISK MANAGEMENT• Prospects for continued

exclusion ?• Management options /

prospects for eradication• (Consultation)CONCLUSION

UK PRA STAGE 1: INITIATION

1. What is the name of the pest? 2. What is the reason for the PRA?

– New pathway ?– New pest ?– New pest ?– New policy ?

3. What is the PRA area? – The UK or European Union?– EPPO region?

PRA areas: the UK

PRA areas: the EU

PRA areas: the EPPO region

A. Pathway-initiated PRAs

• Commonly as a result of a new tradepathway(s), or via

• Identification of a pathway that presents a potential pest risk

• Uses a pathway (rather than a pest) as the • Uses a pathway (rather than a pest) as the basis for the PRA

• Additional PRA’s are necessary for any pests that are identified as potential quarantine pests

Ware potatoes from New Zealand (i)

• PRA initiated via new trade request• Invertebrate potato pests studied

– 52 pests and diseases were found to be common to NZ and UK

– 15 pests identified for PRA– 15 pests identified for PRA• The white fringed weevil , identified as

potentially serious invertebrate for EU• 15 PRAs sent to EC PH Standing Committee

Graphognathus (Naupactus) leucoloma

Conclusion of PRA• polyphagous pest of >350

plant species in the USAincluding vegetable cropsand tree seedlings.and tree seedlings.

• Native to South America• Spread to USA, S. Africa,

Australia & New Zealand• Could spread to the EPPO

region where it wouldthreaten agriculture andsilviculture.

Ware potatoes from New Zealand (ii)

• EC Decision 2001/199/EC– Derogation to import prohibition (Annex III.A.12)– From 1st March to 31st August 2001

• Derogation conditions included– use of certified seed and freedom from the white

fringed weevil, wart disease, brown rot and potato cyst nematodes

– More than 4,500 tonnes were imported– No quarantine pests and diseases detected

B. Pest-initiated PRA

• Uses a pest as the basis for the PRA– All possible pathways need to be considered

• May occur as a result of:– Detection of pest in consignments – Outbreaks - inside or outside of the PRA area– Outbreaks - inside or outside of the PRA area– A request for a pest to be imported for research– The spreading of a pest– Identification of an organism not previously known to

be a pest– Identification of a pest that may require

phytosanitary measures

C. Policy-initiated PRA

• As a result of review or revision of existing phytosanitary policies and priorities

UK PRA STAGE 2: PEST RISK ASSESSMENT

4. Does the pest occur in the PRA area or does itarrive regularly as a natural migrant?– Natural migrants may not be excluded

5. Is …the pest is already established in the PRAarea?area?– PRA may not be required (or for smaller area)

6. What is the pest’s status in thePlant Health Directive (2000/29/EC)?– Quarantine status (listed?)

EC Plant Health Directive 2000/29/EC

• Quarantine pests are listed in the Annexes of the EC Plant Health Directive:-

• 300+ plant viruses, bacteria, insects, mites, nematodes • 300+ plant viruses, bacteria, insects, mites, nematodes and parasitic plants

• Harmful to plants, or plant products, whose Introduction into EU MS’s is banned

• Enacted in the UK by the Plant Health (England) Order 2005

UK PRA STAGE 2: PEST RISK ASSESSMENT (i)

7. What is the quarantine status of the pest in the lists of the European and Mediterranean Plant Protection Organisation (EPPO)?– I.e. EPPO A1 and A2 Lists of pests

8. What are the pests’ host plants ? 8. What are the pests’ host plants ? – Some hosts may not be present (tea in the UK!)

9. What hosts are of economic and/or environmental importance in the PRA area?

UK PRA STAGE 2: PEST RISK ASSESSMENT (ii)

10. If the pest needs a vector , is it present in the PRA area? – Pine wood nematode vectors: Monochamus spp.

11. What is the pest’s present geographical 11. What is the pest’s present geographical distribution ?– Distributions of quarantine pests are given on

EPPO data sheets as well as PRAs

UK PRA scheme

• The previous questions (Q’s 1-11) were aimed at collecting and collating the information required for a PRA

• In the next stages (Q’s 12-19), more judgements are involved: i.e. in making assessments of the likelihood of occurrence a range of factors….

UK PRA STAGE 2: PEST RISK ASSESSMENT (iii)

12. How likely is the pest to enter the PRA area? – Very unlikely – Unlikely – Unlikely – Moderate likelihood – Likely – Very likely

Factors determining the ‘probability of entry’

• The number and variety of pathways• Association of pest with the pathway• Survival in transit• Probability of surviving phytosanitary • Probability of surviving phytosanitary

procedures• Probability of surviving cultural or

commercial practices• Transfer onto a suitable host

UK PRA STAGE 2: PEST RISK ASSESSMENT (iv)

13. How likely is the pest to establish outdoors in the PRA area? – E.g. using CLIMEX mapping to predict

survival

14. How likely is the pest to establish in protected (e.g. glasshouse) environments in the PRA area?– E.g. chrysanthemum glasshouses average of

20-22°C

Factors determining the ‘probability of establishment’

• Ecological Factors– Suitability of the abiotic environment– Presence of suitable hosts, alternate hosts and

vectors– Availability of effective natural or artificial control – Availability of effective natural or artificial control

mechanisms– Cultural practices

• Intrinsic Factors– Life cycle– Reproductive strategy– Genetic adaptability– Minimum population needed for establishment

15.0

20.0

25.0

30.0

35.0

Tem

p (C

)Temperature data in relation to

Aphid nerii development

0.0

5.0

10.0

15.0

1 31 61 91 121 151 181 211 241 271 301 331 361

Julian date

Tem

p (C

)

Heated max Heated min Outdoors max Outdoors minRed = threshold temperature for development of Aphis nerii (8.2°C)

Blue = outdoor maximum and minimum temperature data southern England

Black = maximum and minimum temperature in a heated glasshouse.

Aphis nerii: PRA conclusions

• In the UK hosts are grown outdoors and in protection

• Is a pest which could survive in protection ‘year survive in protection ‘year round’ and outdoors in the summer

• Could be a virus vector• Statutory action was taken

against the pest

Fig. A3(iv) Diabrotica virgifera virgifera distribution in Europepredicted by CLIMEX with 1931-1960 mean climatic data from 285 weather stations

Western corn rootwom: Establishment potential

Average(1997)

Hot(1995)

UK PRA STAGE 2: PEST RISK ASSESSMENT (v)

15. How quickly could the pest spreadwithin the PRA area?

• E.g. For WCR spreading in the UK– A. Without EC controls : Rapid spread– A. Without EC controls : Rapid spread

• 40 km yr -1 rate and costs between £2.2 - 2.6 million over 20 yr

– B. With EC controls : Slow spread• 4 km yr -1 rate and costs between £8.6 - 11.5

million over 20 yr

Maize distribution and Diabrotica spread potential

UK PRA STAGE 2: PEST RISK ASSESSMENT (vi)

16. What is the pest’s potential to cause economic and/or environmental damage in the PRA area?– E.g. Phytophthora ramorum– E.g. Phytophthora ramorum

17. What is the pest’s potential as a vector of plant pathogens?– E.g. Bemisa tabaci: vector of 120+ viruses

Factors determining ‘economic impacts’

• Direct Pest Effects– Yield– Quality– Cost and Efficacy of Plant Protection

• Indirect Pest Effects– Market Access– Environmental Effects– Eradication, Research and Advisory costs– Social costs e.g. tourism

UK PRA STAGE 3: PEST RISK MANAGEMENT (i)

18. How likely is the pest to continue to be excluded from the PRA area?– A) Outdoors and B) In protection

19. How likely are outbreaks to be eradicated ?19. How likely are outbreaks to be eradicated ?– Thrips palmi was eradicated in the UK in 2000-01– Bemisa tabaci is regularly eradicated from

glasshouses in the UK

UK PRA STAGE 3: PEST RISK MANAGEMENT (ii)

20. What management options are available for containment and control?

21. Summary22. Conclusions22. ConclusionsREFERENCESName of Pest Risk Analyst

Conclusion of Pest Risk Assessment

• Provide a statement summarising the overall risk• Does the pest have the characteristics of a

quarantine pest?• Highlight key factors influencing overall risk:

Entry, Establishment, ImpactsEntry, Establishment, Impacts• List the principal uncertainties• Ensure conclusions can easily be used by risk

managers, e.g. EPPO Report of a PRA

Some examples of UK PRA’son the ‘web’ (i)

http://www.fera.defra.gov.uk/plants/plantHealth/pes tsDiseases/praTableNew.cfm

• Citrus longhorned beetle (Anoplophora chinensis)• Cercospora leaf blight of carrot (Cercospora carotae) • Rosemary beetle (Chrysolina americana)• Rosemary beetle (Chrysolina americana)• Tasmanian eucalyptus leaf beetle (Chrysophtharta

bimaculata) • Western Corn Rootworm (Diabrotica v. virgifera)• Phytophthora ramorum and P. kernoviae• Pepino mosaic virus • Chilli thrips (Scirtothrips dorsalis)• Karnal bunt (Tilletia indica)

UK PRAs on the ‘www’ (ii):Consultation

• Hosts and/or sector potentially affected– A specific host; Protected ornamentals; etc.

• Key factors – E.g. already established; absent from UK; etc.

• Current Defra PH recommendations• Current Defra PH recommendations– E.g. Request listing; no statutory action etc.

• Stakeholder action – Comments welcome; subject to – consultation etc.

http://www.defra.gov.uk/planth/pratab.htm

The EPPO PRA scheme:overview

Initiation stage:– WHY? reasons for performing PRA– WHAT? identity of organism– WHERE? definition of PRA area

• Section A: Is there a Risk? • Section A: Is there a Risk? – qualitative assessment if organism is a pest and

presents risk to PRA area

• Section B: How large is the Risk? – quantitative assessment of the risk

• Final evaluation: expert judgement

EPPO Guidelines on pest risk analysis (PRA)

1. PM 5/1(1). Checklist of information required for pest risk analysis (PRA). EPPO Bulletin 23, 191–198.

2. PM 5/2 (revised) . Pest risk analysis on detection of a pest in an imported consignment. detection of a pest in an imported consignment. EPPO Bulletin 32, 235–239.

3. PM 5/3(1). Pest risk assessment scheme. EPPO Bulletin 27 , 281–305.

4. PM 5/4(1). Pest risk management scheme. EPPO Bulletin 31, 11–28.

http://www.eppo.org/QUARANTINE/Pest_Risk_Analysis/PRA_intro.htm

EPPO PRA SCHEME:48 Questions

• Stage 1: Initiation • Stage 2: Pest Risk Assessment

– Section A : Pest categorization– Section B: Assessment of the probability of introduction and

spread and of potential economic consequencesspread and of potential economic consequences• Probability of introduction

– Probability of entry of a pest– Probability of Establishment– Probability of spread

• Assessment of potential economic consequences

• Stage 3: Pest risk management

PEST RISK ANALYSIS SCHEME

Detailed pest risk assessment needed?

Establishment

Spread

Entry

Spread

Analysis of risk management options

Impacts

Pest/pathway risk assessment conclusions

Risk Communication

Section A: Pest categorization

1. Identify the pest 2. Is it a pest in its area of current distribution?3. Does the pest occur (and is it widespread) in

the PRA area?4. Potential for establishment and spread4. Potential for establishment and spread

– Hosts/vectors/ ecoclimatic conditions

5. Potential for economic consequences6. Conclusion : could present a risk OR not a

quarantine pest for the PRA area?

Section B: Probability of introduction (i)

• Probability of entry of a pest• Identification of pathways• Probability of the pest being associated with the

individual pathway at origin• Probability of survival during transport or storage• Probability of survival during transport or storage• Probability of the pest surviving existing pest

management procedures• Consideration of further pathwaysConclusion on the probability of entry

Section B: Probability of introduction (ii)

• Probability of Establishment• Availability of suitable hosts or suitable

habitats , alternate hosts and vectors in the PRA area

• Suitability of the environment• Suitability of the environment• Cultural practices and control measures• Other characteristics of the pest affecting the

probability of establishmentConclusion on the probability of establishment

Section B: Probability of introduction (iii)

• Probability of spread– by natural means? by human assistance?– Conclusion on the probability of spread

• Overall conclusions on the probability of • Overall conclusions on the probability of introduction and spread– E.g. in comparison with PRAs on other pests.

• Conclusion regarding endangered areas– I.e. whole of the PRA area, or parts of it

Assessment of potential economic consequences (i)

Pest effects (in current range and PRA area)• effects on crop yield and/or quality etc.• increase in production costs (incl. control

costs)• reduction in consumer demand• reduction in consumer demand• environmental and social damage • losses in export markets• How easily can the pest be controlled in the

PRA area?

Assessment of potential economic consequences (ii)

• Would control measures disrupt existingbiological or integrated systems?

• other costs resulting from introduction?• Could genetic traits be transferred to other• Could genetic traits be transferred to other

species?• Act as a vector or host for other pests?• Conclusion of the assessment of economic

consequences

EPPO PRA SCHEME:Conclusions

• Conclusion of the pest risk assessment – Entry– Establishment – Economic importance– Economic importance

• Overall conclusion of the Pest Risk Assessment

• Stage 3: Pest risk management– Covered in 2nd talk

Pest Risk Communication (i)

• Not a discrete stage of PRA• Continuous throughout PRA

– Ensures views of all parties are taken into consideration when making decisionsconsideration when making decisions

– If all information is shared, government and stakeholders will often reach the same conclusions

– International harmonization

• Purpose is to reconcile the views of scientists, stakeholders, politicians, etc in order to:– Achieve a common understanding of the pest risks– Develop credible pest risk management options

Pest Risk Communication (ii)

– Develop credible and consistent regulations and policies to deal with pest risks

– Promote awareness of the phytosanitary issues under consideration

EFSA

• The European Food Safety Authority (EFSA) • Responsible for European Union (EU) risk

assessment regarding food and feed safety• New Panel on Plant Health (PLH) • New Panel on Plant Health (PLH) • Remit is to peer review and assess risks

associated with plant pests in EU• The Panel on Plant Health (PLH) deals with

organisms posing a risk to plant health. The Panel is supported by the Plant Health Unit. http://www.efsa.europa.eu/en/panels/plh.htm6

Uncertainty

• Uncertainty of the process (methodology)• Uncertainty of the assessor(s) (human errors)• Uncertainty of the organisms (biological unknowns)• The goal of PRA is to reduce the uncertainties

– Formalised procedures, checklists and established – Formalised procedures, checklists and established precedents all help to reduce uncertainty

– PRAs providing a transparent process available for scrutiny and discussion

– Uncertainties may remain and it is the role of the assessor to highlight these as an aid to decision/policy making