Being prepared for huanglongbing disease of citrus: a simulation exercise workshop for contingency planning held in Valencia, Spain

Abstract

Contingency plans aim to ensure a rapid and effective response to an outbreak of a pest likely which is to have a major impact. Huanglongbing is a devastating disease of citrus not yet present in the European and Mediterranean Plant Protection Organization (EPPO) region. A simulation exercise workshop for contingency planning was held in Valencia, Spain over 3 days in October 2021 as part of the PRE‐HLB project funded by the European Union Horizon 2020 programme. In total, 49 experts from the EPPO region attended the workshop. Participants represented a range of stakeholders from citrus cooperatives, grower associations, nursery workers, citrus exporters, landscapers and gardeners, scientists, Regional Plant Health Authorities, National Plant Protection Organizations and the European Commission. Participants were split into five groups and each group acted as an outbreak management team for a scenario based on a finding of a quarantine pest. The scenario followed the first (fictitious) finding of Diaphorina citri (the insect vector of ‘Candidatus Liberibacter asiaticus’, a causal agent of huanglongbing) at a citrus orchard in Spain. As the scenario developed over a month time scale, each team had to organize themselves to manage a number of issues designed to mimic the development of an outbreak of huanglongbing of citrus over the course of the exercise. The groups acknowledged the usefulness of the Spanish contingency plans for huanglongbing and its vectors, the EPPO Standards, and the risk‐based surveillance design tool RiBESS+.

The African citrus psyllid Trioza erytreae: An efficient vector of Candidatus Liberibacter asiaticus

“…This area is then at high risk if the bacteria is introduced, consequences would be tremendously important knowing that this region, still HLB-free, is the 5 th worldwide citrus producer, after China, the USA, Brazil, and India ( FAO, 2021 ).Furthermore, a recent study has proven also the risk of the potential introduction of this vector in high citrus growing areas of Mexico that would be most suitable for this vector than D. citri with C Las already present ( Espinosa-Zaragoza et al., 2021 ). Preventive measures and an action plans were proposed in previous studies to reduce the risk of introduction and/or establishment of C Las and C Laf in the Mediterranean area ( Durán-Vila et al., 2014 ; Aragón et al., 2022 ). Thus, in the light of the results of our study and the recent increase in the range of T. erytreae , these proposed measures should be taken into account even more.…”

Risk-based regionalization approach for area-wide management of HLB vectors in the Mediterranean Basin

“…As in Galvañ et al (2022), relative humidity (RH) as a percentage was calculated according to Wallace and Hobbs (2006) using air and dew point temperatures as follows:…”

“…These EU priority pests are the ones with the highest potential socioeconomic impact. They are subjected to additional mandatory phytosanitary measures including annual surveys, contingency and action plans, simulation exercises, and public information ( European Union (EU), 2016 ; Aragón et al., 2022 ). Despite the phytosanitary regulations, over the last few years several interceptions of ACP at the EU borders have been reported.…”

“…The Spanish National Plant Protection Organization (NPPO) developed contingency plans for HLB and its vectors ( Ministerio de Agricultura, Pesca y Alimentación (MAPA), 2021a ; Ministerio de Agricultura, Pesca y Alimentación (MAPA), 2021b ; Ministerio de Agricultura, Pesca y Alimentación (MAPA), 2023a ). These contingency plans were recently evaluated in a simulation exercise ( Aragón et al., 2022 ) and have been translated to a specific regulation to address the control and eradication of the AfCP and to prevent the introduction of the ACP and C Ls ( Ministerio de Agricultura, Pesca y Alimentación (MAPA), 2023b ). Nevertheless, how to organize citrus growers in order to coordinate vector control through area-wide management is not specifically addressed in this contingency plan.…”

Developing epidemiological preparedness for a plant disease invasion: modelling citrus huánglóngbìng in the European Union

“…Both the recent detections of ACP in Israel and Cyprus and the established presence of AfCP in Spain and Portugal are concerning, since either vector could facilitate HLB transmission were a pathogen to be introduced (Cocuzza et al, 2017). Although contingency plans for the arrival of HLB in Spain and Portugal exist (DGAV, 2021; BOE, 2023), and have been tested in formal simulation exercises (Aragón et al, 2022), designing an effective response is challenging. Management interventions that have been used somewhat successfully in other areas might not translate to the EU, since important epidemiological aspects are different.…”