European Union Reference Laboratory for Escherichia coli including VTEC, Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
Int J Food Microbiol. 2019 Jan 2;288:53-57. doi: 10.1016/j.ijfoodmicro.2018.05.005. Epub 2018 May 8.
In 2006, the European Committee for standardisation (CEN)/Technical Committee 275 - Food analysis - Horizontal methods/Working Group 6 - Microbiology of the food chain (TC275/WG6), launched the project of validating the method ISO 16654:2001 for the detection of Escherichia coli O157 in foodstuff by the evaluation of its performance, in terms of sensitivity and specificity, through collaborative studies. Previously, a validation study had been conducted to assess the performance of the Method No 164 developed by the Nordic Committee for Food Analysis (NMKL), which aims at detecting E. coli O157 in food as well, and is based on a procedure equivalent to that of the ISO 16654:2001 standard. Therefore, CEN established that the validation data obtained for the NMKL Method 164 could be exploited for the ISO 16654:2001 validation project, integrated with new data obtained through two additional interlaboratory studies on milk and sprouts, run in the framework of the CEN mandate No. M381. The ISO 16654:2001 validation project was led by the European Union Reference Laboratory for Escherichia coli including VTEC (EURL-VTEC), which organized the collaborative validation study on milk in 2012 with 15 participating laboratories and that on sprouts in 2014, with 14 participating laboratories. In both studies, a total of 24 samples were tested by each laboratory. Test materials were spiked with different concentration of E. coli O157 and the 24 samples corresponded to eight replicates of three levels of contamination: zero, low and high spiking level. The results submitted by the participating laboratories were analyzed to evaluate the sensitivity and specificity of the ISO 16654:2001 method when applied to milk and sprouts. The performance characteristics calculated on the data of the collaborative validation studies run under the CEN mandate No. M381 returned sensitivity and specificity of 100% and 94.4%, respectively for the milk study. As for sprouts matrix, the sensitivity resulted in 75.9% in the low level of contamination samples and 96.4% in samples spiked with high level of E. coli O157 and specificity was calculated as 99.1%.
2006 年，欧洲标准化委员会（CEN）/食品分析技术委员会 275-食物链微生物学/第 6 工作组（TC275/WG6）启动了验证 ISO 16654：2001 方法的项目，该方法用于检测食品中的大肠杆菌 O157，通过协作研究评估其灵敏度和特异性。在此之前，已经进行了一项验证研究，以评估北欧食品分析委员会（NMKL）制定的方法 No 164 的性能，该方法也旨在检测食品中的大肠杆菌 O157，其基础程序等同于 ISO 16654：2001 标准。因此，CEN 确定可以利用为 NMKL 方法 164 获得的验证数据来为 ISO 16654：2001 验证项目提供支持，这些数据与通过在 CEN 任务 No. M381 框架内进行的两项关于牛奶和豆芽的额外实验室间研究获得的新数据相结合。ISO 16654：2001 验证项目由欧盟大肠杆菌包括肠出血性大肠杆菌（EURL-VTEC）参考实验室领导，该实验室于 2012 年组织了牛奶协作验证研究，共有 15 个参与实验室，于 2014 年组织了豆芽协作验证研究，共有 14 个参与实验室。在这两项研究中，每个实验室共测试了 24 个样本。测试材料中添加了不同浓度的大肠杆菌 O157，24 个样本对应于三个污染水平的 8 个重复：零、低和高添加水平。对参与实验室提交的结果进行分析，以评估 ISO 16654：2001 方法应用于牛奶和豆芽时的灵敏度和特异性。根据在 CEN 任务 No. M381 下运行的协作验证研究的数据计算出的性能特征，牛奶研究的灵敏度和特异性分别为 100%和 94.4%。对于豆芽基质，低污染水平样本的灵敏度为 75.9%，高浓度大肠杆菌 O157 样本的灵敏度为 96.4%，特异性计算为 99.1%。
