An updated assessment of the risks to plant health posed Xylella fastidiosain the EU territory

Trabajo presentado en la 2nd European conference on Xylella fastidiosa (how research can support solutions), celebrada en Ajaccio el 29 y 30 de octubre de 2019.EFSA received a request from the European Commission to update its 2015 Pest Risk Assessment (PRA) for Xylella fastidiosa in the EU territory. The update focused on potential establishment, short and long-range spread, the length of the asymptomatic period, the impact of X. fastidiosaand an update on risk reduction options, accounting for the different subspecies and Sequence Types of X. fastidiosaduring the risk assessment where data availability allowed. Here we summarise the main conclusions of the updated PRA, the uncertainties associated with the conclusions, and recommended futuredirections for research and data collection to reduce these uncertainties. The quantitative PRA provided new insights on containing existing outbreaks and preventing further spread in the EU. For example, it was demonstrated that most of the EU has potential climatic suitability for Xylella but that the southern EU is most at risk;however,X. fastidiosasubsp. multiplexdemonstrated areas of potential establishment further north in Europe compared with other subspecies. Modelling was also used to assess data from a wide range of studies on the length of the asymptomatic period, as well as to simulate the spread of the disease and management measures aimed at eradicating or containing the pathogen. The assessment showed the importance of disease control measures, including the use of buffer zones and plant removal, but also the need to couple these measures with effective vector control, rapid implementation of management measures following disease discovery, and early detection of new positive cases. The latter issue is a particular challenge for Xylellagiven the length of the asymptomatic period, particularly for some host and subspecies combinations. In a separate mandate EFSA is developing new surveillance guidelines for Xylellato enable for more effective and targeted detection surveys for the disease.Peer reviewe