VanA-type human (n ‫؍‬ 69), animal (n ‫؍‬ 49), and food (n ‫؍‬ 36) glycopeptide-resistant enterococci (GRE) from different geographic areas were investigated to study their possible reservoirs and transmission routes. Pulsed-field gel electrophoresis (PFGE) revealed two small genetically related clusters, M39 (n ‫؍‬ 4) and M49 (n ‫؍‬ 13), representing Enterococcus faecium isolates from animal and human feces and from clinical and fecal human samples. Multilocus sequence typing showed that both belonged to the epidemic lineage of CC17. purK allele analysis of 28 selected isolates revealed that type 1 was prevalent in human strains (8/11) and types 6 and 3 (14/15) were prevalent in poultry (animals and meat). One hundred and five of the 154 VanA GRE isolates, encompassing different species, origins, and PFGE types, were examined for Tn1546 type and location (plasmid or chromosome) and the incidence of virulence determinants. Hybridization of S1-and I-CeuI-digested total DNA revealed a plasmid location in 98% of the isolates. Human intestinal and animal E. faecium isolates bore large (>150 kb) vanA plasmids. Results of PCR-restriction fragment length polymorphism and sequencing showed the presence of prototype Tn1546 in 80% of strains and the G-to-T mutation at position 8234 in three human intestinal and two pork E. faecium isolates. There were no significant associations (P > 0.5) between Tn1546 type and GRE source or enterococcal species. Virulence determinants were detected in all reservoirs but were significantly more frequent (P < 0.02) among clinical strains. Multiple determinants were found in clinical and meat Enterococcus faecalis isolates. The presence of indistinguishable vanA elements (mostly plasmid borne) and virulence determinants in different species and PFGE-diverse populations in the presence of host-specific purK housekeeping genes suggested that all GRE might be potential reservoirs of resistance determinants and virulence traits transferable to human-adapted clusters.

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EFSA carries out the risk assessment of genetically modified organisms (GMOs) submitted under Regulation (EC) 1829/2003 and Regulation (EU) 503/2013. Dietary exposure is an essential element of the risk assessment on genetically modified (GM) foods. Dietary exposure estimations should cover average and high consumers across all the different age classes and special population groups and identify and consider particular consumer groups with expected higher exposure. This EFSA statement provides guidance on how human dietary exposure to newly expressed proteins in GM foods should be estimated using a deterministic model that makes use of the available information. Summary statistics of consumption of foods containing, consisting of and produced from crops relevant for the assessment of GMO applications are available in the EFSA website together with different factors to convert the reported consumption of processed foods into raw primary commodities. Guidance is also provided on how concentration data of newly expressed proteins, typically determined in raw primary commodities, should be used (materials to be analysed, growth stage, descriptive statistics to be used, etc.). An overview of the different uncertainties linked to the dietary exposure estimations is provided, informing on the strengths and limitations of the assessment. The document also describes the information applicants need to provide on human dietary exposure to allow EFSA doing an appropriate evaluation of the assessment provided as part of the application dossiers.

BackgroundSafety assessment of genetically modified organisms is currently often performed by comparative evaluation. However, natural variation of plant characteristics between commercial varieties is usually not considered explicitly in the statistical computations underlying the assessment.ResultsStatistical methods are described for the assessment of the difference between a genetically modified (GM) plant variety and a conventional non-GM counterpart, and for the assessment of the equivalence between the GM variety and a group of reference plant varieties which have a history of safe use. It is proposed to present the results of both difference and equivalence testing for all relevant plant characteristics simultaneously in one or a few graphs, as an aid for further interpretation in safety assessment. A procedure is suggested to derive equivalence limits from the observed results for the reference plant varieties using a specific implementation of the linear mixed model. Three different equivalence tests are defined to classify any result in one of four equivalence classes. The performance of the proposed methods is investigated by a simulation study, and the methods are illustrated on compositional data from a field study on maize grain.ConclusionsA clear distinction of practical relevance is shown between difference and equivalence testing. The proposed tests are shown to have appropriate performance characteristics by simulation, and the proposed simultaneous graphical representation of results was found to be helpful for the interpretation of results from a practical field trial data set.

Genetically modified organisms (GMOs) and derived food and feed products are subject to a risk analysis and regulatory approval before they can enter the market in the European Union (EU). In this risk analysis process, the role of the European Food Safety Authority (EFSA), which was created in 2002 in response to multiple food crises, is to independently assess and provide scientific advice to risk managers on any possible risks that the use of GMOs may pose to human and animal health and the environment. EFSA's scientific advice is elaborated by its GMO Panel with the scientific support of several working groups and EFSA's GMO Unit. This review presents EFSA's scientific activities and highlights its achievements on the risk assessment of GMOs for the first 10 years of its existence. Since 2002, EFSA has issued 69 scientific opinions on genetically modified (GM) plant market registration applications, of which 62 for import and processing for food and feed uses, six for cultivation and one for the use of pollen (as or in food), and 19 scientific opinions on applications for marketing products made with GM microorganisms. Several guidelines for the risk assessment of GM plants, GM microorganisms and GM animals, as well as on specific issues such as post-market environmental monitoring (PMEM) were elaborated. EFSA also provided scientific advice upon request of the European Commission on safeguard clause and emergency measures invoked by EU Member States, annual PMEM reports, the potential risks of new biotechnology-based plant breeding techniques, evaluations of previously assessed GMOs in the light of new scientific publications, and the use of antibiotic resistance marker genes in GM plants. Future challenges relevant to the risk assessment of GMOs are discussed. EFSA's risk assessments of GMO applications ensure that data are analysed and presented in a way that facilitates scientifically sound decisions that protect human and animal health and the environment.