103 research outputs found
A New Online Resource to Monitor New or Emerging Plant Pests: MEDISYS Media Monitoring and the Case of Xylella fastidiosa.
The European Food Safety Authority has established a horizon scanning exercise for plant pests by automated monitoring of open-source media. The news sources are screened using the publicly accessible MEDISYS (Medical Information System) platform of the Joint Research Centre of the European Commission. Here, we report the example of monitoring for Xylella fastidiosa, a highly polyphagous plant-pathogenic bacterium. Since its first occurrence in Europe, news sources have reported findings and latest developments. Media monitoring-related data can support surveillance or plant pests' management programs by early warning and can help understand the impacts of plant pests and the societal response to new plant health threats
A New Resource for Research and Risk Analysis: The Updated European Food Safety Authority Database of Xylella spp. Host Plant Species.
Following a series of requests for scientific advice from the European Commission starting in 2013, the European Food Safety Authority (EFSA) conducted a pest risk assessment and created a comprehensive Xylella fastidiosa host plant database. The last update of the database, published in September 2018, includes information on host plants of both X. fastidiosa and X. taiwanensis, together with details on botanical classification, infection conditions, geographic location, pathogen taxonomy including information on subspecies, strain and sequence type, detection techniques, and tolerant/resistant response of the plant. This updated database of host plants of Xylella spp. reported worldwide provides a key tool for risk management, risk assessment, and research on this generalist bacterial plant pathogen
6MWT performance correlates with peripheral neuropathy but not with cardiac involvement in patients with hereditary transthyretin amyloidosis (hATTR)
Abstract Hereditary transthyretin amyloidosis (hATTR) is a life-threatening multisystemic disease with sensory-motor peripheral neuropathy, cardiomyopathy and dysautonomia. Although the six-minute walk test (6MWT) is one of the most popular clinical tests to assess functional exercise capacity in cardiopulmonary and neuromuscular diseases, little is known about 6MWT in evaluating hATTR patients. A prospective single-center pilot study was performed in twenty hATTR patients, comparing 6MWT with widely used outcome measures. After 18 months, fourteen patients were re-evaluated. 6MWT performance was highly related with familial amyloidotic polyneuropathy stage and polyneuropathy disability score, and with CMT examination score, neuropathy impairment score-lower limbs and Kumamoto score. There was no correlation with compound autonomic dysfunction test, modified body mass index and numerous indices of heart dysfunction. After 18 months, familial amyloidotic polyneuropathy stage and polyneuropathy disability score systems were not able to reveal any significant change, whereas all other outcome measures significantly worsened. Among the outcome measures monitoring the neuropathic disturbances, neuropathy impairment score-lower limbs showed the highest responsiveness to change (adjusted effect size: 0.79), followed by CMT examination score (0.67), Kumamoto scale (0.65), 6MWT (0.62). 10MWT showed a very small value (0.21). Compound autonomic dysfunction test had a large value (0.91) whereas modified body mass index a small/moderate value (0.49). 6MWT is a simple and sensitive tool to monitor neuropathic involvement but not cardiac dysfunction in hATTR course
On the use of antibiotics to control plant pathogenic bacteria: a genetic and genomic perspective
Despite growing attention, antibiotics (such as streptomycin, oxytetracycline or kasugamycin) are still used worldwide for the control of major bacterial plant diseases. This raises concerns on their potential, yet unknown impact on antibiotic and multidrug resistances and the spread of their genetic determinants among bacterial pathogens. Antibiotic resistance genes (ARGs) have been identified in plant pathogenic bacteria (PPB), with streptomycin resistance genes being the most commonly reported. Therefore, the contribution of mobile genetic elements (MGEs) to their spread among PPB, as well as their ability to transfer to other bacteria, need to be further explored. The only well-documented example of ARGs vector in PPB, Tn5393 and its highly similar variants (carrying streptomycin resistance genes), is concerning because of its presence outside PPB, in Salmonella enterica and Klebsiella pneumoniae, two major human pathogens. Although its structure among PPB is still relatively simple, in human- and animal-associated bacteria, Tn5393 has evolved into complex associations with other MGEs and ARGs. This review sheds light on ARGs and MGEs associated with PPB, but also investigates the potential role of antibiotic use in resistance selection in plant-associated bacteria
Evaluation of a paper by Guarnaccia et al. (2017) on the first report of Phyllosticta citricarpa in Europe
27The Plant Health Panel reviewed the paper by Guarnaccia et al. (2017) and compared theirfindingswith previous predictions on the establishment ofPhyllosticta citricarpa. Four species ofPhyllostictawere found by Guarnaccia et al. (2017) in Europe.P. citricarpaandP. capitalensisare well-definedspecies, withP. citricarparecorded for thefirst time in Europe, confirming predictions by Magareyet al. (2015) and EFSA (2008, 2014, 2016) thatP. citricarpacan establish in some European citrus-growing regions. Two new speciesP. paracitricarpaandP. paracapitalensiswere also described, withP. paracitricarpa(found only in Greece) shown to be pathogenic on sweet orange fruits.Genotyping oftheP. citricarpaisolates suggests at least two independent introductions, with the population inPortugal being different from that present in Malta and Italy.P. citricarpaandP. paracitricarpawereisolated only from leaf litter in backyards. However, sinceP. citricarpadoes not infect or colonise deadleaves, the pathogen must have infected the above living leaves in citrus trees nearby. Guarnacciaet al. (2017) considered introduction to be a consequence ofP. citricarpahaving long been present orof illegal movement of planting material. In the Panelâs view, the fruit pathway would be an equally ormore likely origin. The authors did not report how surveys for citrus black spot (CBS) disease werecarried out, therefore their claim that there was no CBS disease even where the pathogen was presentis not supported by the results presented. From previous simulations, the locations where Guarnacciaet al. (2017) foundP. citricarpaorP. paracitricarpawere conducive forP. citricarpaestablishment, withnumber of simulated infection events by pycnidiospores comparable to sites of CBS occurrence outsideEurope. Preliminary surveys by National Plant Protection Organisations (NPPOs) have not confirmed sofar thefindings by Guarnaccia et al. (2017) but monitoring is still ongoingopenopenJeger, Michael; Bragard, Claude; Caffier, David; Candresse, Thierry; Chatzivassiliou, Elisavet; DehnenâSchmutz, Katharina; Gilioli, Gianni; GrĂ©goire, JeanâClaude; Jaques Miret, Josep Anton; MacLeod, Alan; Navajas Navarro, Maria; Niere, Björn; Parnell, Stephen; Potting, Roel; Rafoss, Trond; Rossi, Vittorio; Urek, Gregor; Van Bruggen, Ariena; Van Der Werf, Wopke; West, Jonathan; Winter, Stephan; Baker, Richard; Fraaije, Bart; Vicent, Antonio; Behring, Carsten; Mosbach Schulz, Olaf; Stancanelli, GiuseppeJeger, Michael; Bragard, Claude; Caffier, David; Candresse, Thierry; Chatzivassiliou, Elisavet; Dehnenâschmutz, Katharina; Gilioli, Gianni; GrĂ©goire, Jeanâclaude; Jaques Miret, Josep Anton; Macleod, Alan; Navajas Navarro, Maria; Niere, Björn; Parnell, Stephen; Potting, Roel; Rafoss, Trond; Rossi, Vittorio; Urek, Gregor; Van Bruggen, Ariena; Van Der Werf, Wopke; West, Jonathan; Winter, Stephan; Baker, Richard; Fraaije, Bart; Vicent, Antonio; Behring, Carsten; Mosbach Schulz, Olaf; Stancanelli, Giusepp
Effectiveness of in planta control measures for Xylella fastidiosa
This opinion updates the information included in the previous EFSA Scientific Opinion concerning the
in planta control measures for Xylella fastidiosa, with a systematic review and critical analysis of
the potential treatment solutions that have been published against this pest so far. The output of this
opinion focuses on the application of chemical or biological treatments on living plants. In vitro studies,
hot water treatments, use of resistant varieties and vector control are excluded from the review. The
use of antibiotics is not considered due to the risk of antimicrobial resistance development. The use of
weakly virulent or avirulent strains of X. fastidiosa is covered in this review, although this organism is
an EU quarantine plant pest and its introduction in the EU territory is banned. Experiments were
recently conducted to assess the effect of application of zinc, copper, and citric acid biocomplex, of
N-acetylcysteine, and of âdiffusible signal factorâ (and of its homologs). Their results showed that these
control measures were sometimes able to reduce symptoms caused by X. fastidiosa. Recent
experiments also showed that several species of endophytic microorganisms, some bacteriophages and
inoculation of weakly virulent/avirulent strains of X. fastidiosa could offer some protection against the
Pierceâs disease. However, based on the reviewed results, the Panel concludes that, although several
published experiments show some effects in reducing symptoms development, the tested control
measures are not able to completely eliminate X. fastidiosa from diseased plants. The Panel confirms
as previously stated that there is currently no control measure available to eliminate the bacteria from
a diseased plant in open field conditions
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
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