Johnson Ronald L, Jechorek Robert P
bioMérieux, Inc., 595 Anglum Rd, Hazelwood, MO 63042-2320, USA.
J AOAC Int. 2011 Jan-Feb;94(1):159-71.
In a multilaboratory study, the effectiveness of an alternative method for rapid screening of Listeria species compared to traditional reference methods was demonstrated in a variety of food products. A collaborative study was conducted to compare the VIDAS Listeria species Xpress (LSX) method and the standard cultural methods for the detection of Listeria species in foods. Six food types were tested: vanilla ice cream, cheddar cheese, raw ground beef, frozen green beans, deli turkey, and cooked shrimp. Each food, inoculated with a different Listeria strain at two levels and uninoculated test portions, was analyzed by each method. A total of 15 laboratories representing government and industry participated. In this study 1134 tests were analyzed in the statistical analysis. There were 490 positives by the VIDAS LSX method using the sample boiling step, 483 positives by the VIDAS LSX method using the Heat and Go system, and 439 positives by the standard culture methods. Overall, the Chi-square result for the VIDAS LSX method with boiling for all foods was 7.25, indicating a significant statistical difference between the VIDAS method and the standard methods at the 5% confidence. For the VIDAS LSX method with the Heat and Go system, the Chi-square result for all foods was 5.37, indicating a significant statistical difference between the VIDAS LSX assay with the Heat and Go system and the standard methods at the 5% level of significance. In both cases, the VIDAS method was more sensitive than the standard methods. The LSX method detects Listeria species in foods with negative or presumptive positive results in a minimum of 30 h compared to at least 5 days for the cultural methods. Based on the results of this collaborative study, it is recommended that the VIDAS LSX method be adopted as an AOAC Official Method for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry.
在一项多实验室研究中，与传统参考方法相比，一种用于快速筛查李斯特菌属的替代方法在多种食品中的有效性得到了验证。开展了一项协作研究，以比较VIDAS李斯特菌属快速检测法（LSX）和用于检测食品中李斯特菌属的标准培养方法。测试了六种食品类型：香草冰淇淋、切达干酪、生牛肉末、冷冻青豆、熟食火鸡和熟虾。每种食品接种两种不同水平的不同李斯特菌菌株，并设置未接种的测试部分，每种方法都对其进行分析。共有15个代表政府和行业的实验室参与。在这项研究中，统计分析共分析了1134次检测。使用样品煮沸步骤的VIDAS LSX方法检测出490个阳性结果，使用热启动系统的VIDAS LSX方法检测出483个阳性结果，标准培养方法检测出439个阳性结果。总体而言，所有食品采用煮沸法的VIDAS LSX方法的卡方检验结果为7.25，表明VIDAS方法与标准方法在5%置信水平上存在显著统计学差异。对于采用热启动系统的VIDAS LSX方法，所有食品的卡方检验结果为5.37，表明采用热启动系统的VIDAS LSX检测法与标准方法在5%显著性水平上存在显著统计学差异。在这两种情况下，VIDAS方法都比标准方法更灵敏。LSX方法检测食品中李斯特菌属的阴性或疑似阳性结果至少需要30小时，而培养方法至少需要5天。基于这项协作研究的结果，建议采用VIDAS LSX方法作为美国官方分析化学师协会（AOAC）检测乳制品、蔬菜、海鲜、生肉和家禽以及加工肉和家禽中李斯特菌属的官方方法。
