ABSTRACT
This scientific report provides an update of the Xylella spp. host plant database, aiming to provide information and scientific support to risk assessors, risk managers and researchers dealing with Xylella spp. Upon a mandate of the European Commission, EFSA created and regularly updates a database of host plant species of Xylella spp. The current mandate covers the period 2021-2026. This report is related to the ninth version of the database published in Zenodo in the EFSA Knowledge Junction community, covering literature published from 1 January 2023 up to 30 June 2023, and recent Europhyt outbreak notifications. Informative data have been extracted from 47 selected publications. Seven new host plants were identified and added to the database. These plant species were naturally infected by X. fastidiosa subsp. multiplex in France, Spain and the United States. No additional data were retrieved for X. taiwanensis, and no additional multilocus sequence tipes (STs) were identified worldwide. New information on the tolerant/resistant response of plant species to X. fastidiosa infection were added to the database. The Xylella spp. host plant species were listed in different categories based on the number and type of detection methods applied for each finding. The overall number of Xylella spp. host plants determined with at least two different detection methods or positive with one method (between sequencing and pure culture isolation (category A), reaches now 439 plant species, 200 genera and 69 families. Such numbers rise to 696 plant species, 307 genera and 88 families if considered regardless of the detection methods applied (category E).
ABSTRACT
Piperacillin/tazobactam (TZP) is a ß-lactam/ß-lactamase inhibitor (BL/BLI) recommended for the empirical treatment of severe infections. The excessive and indiscriminate use of TZP has promoted the emergence of TZP-resistant Escherichia coli isolates. Recently, we demonstrated that TZP may contribute to the development of extended-spectrum resistance to BL/BLI (ESRI) in E. coli isolates that are TZP susceptible but have low-level resistance to BL/BLI (resistance to amoxicillin/clavulanic acid [AMC] and/or ampicillin/sulbactam [SAM]). This raises the need for the development of rapid detection systems. Therefore, the objective of this study was to design and validate a method able to detect TZP resistance and ESRI in E. coli. A colorimetric assay based on ß-lactam ring hydrolysis by ß-lactamases was designed (ESRI test). A total of 114 E. coli isolates from bloodstream and intra-abdominal sources, characterized according to their susceptibility profiles to BL/BLI, were used. Detection of the three most frequent ß-lactamases involved in BL/BLI resistance (blaTEM, blaOXA-1, and blaSHV) was performed by PCR. The ESRI test was able to detect all the TZP-intermediate/-resistant isolates, as well as all the TZP-susceptible isolates with a capacity for ESRI development. Their median times to results were 5 and 30 min, respectively. All the isolates without resistance to BL/BLI displayed a negative result in the ESRI test. blaTEM was the most frequent ß-lactamase gene detected, follow by blaSHV and blaOXA-1. These results demonstrate the efficacy of the ESRI test, showing great clinical potential which could lead to reductions in health costs, ineffective treatments, and inappropriate use of BL/BLI. IMPORTANCE TZP is a BL/BLI recommended for the empirical treatment of severe infections. The excessive use of TZP has promoted the emergence of TZP-resistant Escherichia coli isolates. We recently reported that TZP may contribute to the development of ESRI in E. coli isolates that are TZP susceptible but have low-level resistance to BL/BLI. This raises the need for the development of rapid detection systems. Here, we demonstrated that the ESRI test was able to detect the TZP-intermediate or -resistant isolates and the TZP-susceptible isolates with the capacity for ESRI development. All the isolates without BL/BLI resistance were negative for the ESRI test and did not harbor ß-lactamase genes. For ESRI developers and TZP-intermediate or -resistant isolates, blaTEM was the most frequent ß-lactamase gene detected, follow by blaSHV and blaOXA-1. The sensitivity, specificity, and positive and negative predictive values were all 100%. These data demonstrate the efficacy of the ESRI test and show that it has great clinical potential.
