Guidance on quantitative pest risk assessment.

This Guidance describes a two-phase approach for a fit-for-purpose method for the assessment of plant pest risk in the territory of the EU. Phase one consists of pest categorisation to determine whether the pest has the characteristics of a quarantine pest or those of a regulated non-quarantine pest for the area of the EU. Phase two consists of pest risk assessment, which may be requested by the risk managers following the pest categorisation results. This Guidance provides a template for pest categorisation and describes in detail the use of modelling and expert knowledge elicitation to conduct a pest risk assessment. The Guidance provides support and a framework for assessors to provide quantitative estimates, together with associated uncertainties, regarding the entry, establishment, spread and impact of plant pests in the EU. The Guidance allows the effectiveness of risk reducing options (RROs) to be quantitatively assessed as an integral part of the assessment framework. A list of RROs is provided. A two-tiered approach is proposed for the use of expert knowledge elicitation and modelling. Depending on data and resources available and the needs of risk managers, pest entry, establishment, spread and impact steps may be assessed directly, using weight of evidence and quantitative expert judgement (first tier), or they may be elaborated in substeps using quantitative models (second tier). An example of an application of the first tier approach is provided. Guidance is provided on how to derive models of appropriate complexity to conduct a second tier assessment. Each assessment is operationalised using Monte Carlo simulations that can compare scenarios for relevant factors, e.g. with or without RROs. This document provides guidance on how to compare scenarios to draw conclusions on the magnitude of pest risks and the effectiveness of RROs and on how to communicate assessment results.

Pest risk assessment of Radopholus similis for the EU territory.

The Panel on Plant Health performed a pest risk assessment on Radopholus similis, the burrowing nematode for the EU. The quantitative assessment focused on entry, establishment, spread and impact on tropical and subtropical ornamental host plants, the main pathways for entry of R. similis into the EU. Infested consignments are expected to enter the risk assessment area on ornamentals under all scenarios. For citrus, which is a closed pathway for entry, outdoor establishment was assessed. Establishment may only take place after successful transfer from ornamental plants to citrus production systems. This event is called 'shift' in this assessment, to indicate that this is an unusual transfer. It has been estimated that establishment of this nematode in the open field in the EU citrus production areas under current temperatures is possible in most parts of the citrus production area in the EU. Temperature conditions will prevent the nematode from establishing only in the northernmost citrus areas and at higher altitudes in the south. Host plants for planting originating from infested places of production (greenhouses) within the risk assessment area are considered the main pathway for spread within the risk assessment area. Under current climatic conditions, the population of R. similis is not expected to reach damaging population levels in the open field. In case of increased temperatures due to global warming, the nematode population may reach damaging levels in very few places outdoors. Currently, main impact is considered for ornamental greenhouse production in the risk assessment area. Impact will be either caused by direct plant growth reductions or loss due to phytosanitary measures applied on regulated plants. Despite the fact that R. similis is globally considered as one of the most destructive plant parasitic nematodes, the impact in the risk assessment area is considered low.

Drivers for emerging issues in animal and plant health.

The history of agriculture includes many animal and plant disease events that have had major consequences for the sector, as well as for humans. At the same time, human activities beyond agriculture have often driven the emergence of diseases. The more that humans expand the footprint of the global population, encroach into natural habitats, alter these habitats to extract resources and intensify food production, as well as move animals, people and commodities along with the pathogens they carry, the greater the potential for pathogens and pests to spread and for infection to emerge or re-emerge. While essential to human well-being, producing food also plays a major role in disease dynamics. The risk of emergence of pests and pathogens has increased as a consequence of global changes in the way food is produced, moved and consumed. Climate change is likely to increase pressure on the availability of food and provide newly suitable conditions for invasive pests and pathogens. Human population displacements due to economic, political and humanitarian crises represent another set of potential drivers for emerging issues. The overlapping drivers of plant, animal and human disease emergence and environmental changes point towards the concept of 'One Health'. This paradigm underlines the urgent need to understand the influence of human behaviour and incorporate this understanding into our approach to emerging risks. For this, we face two major challenges. One is cultural; the second is methodological. We have to look at systems not under the narrow view of specific hazards but with a wider approach to system dynamics, and consider a broad spectrum of potential outcomes in terms of risk. In addition, we have to make sense of the vast amounts of data that are available in the modern age. This paper aims to help in preparing for the cultural and methodological shifts needed in our approach to emerging risks.