Brito J Renaldi F, Santos Emilia M P, Arcuri Edna F, Lange Carla C, Brito Maria A V P, Souza Guilherme N, Cerqueira Mônica M P O, Beltran J Marcela Soto, Call Jeffrey E, Liu Yanhong, Porto-Fett Anna C S, Luchansky John B
Brazilian Agricultural Research Corporation (Embrapa).
Appl Environ Microbiol. 2008 Aug;74(15):4954-61. doi: 10.1128/AEM.01828-07. Epub 2008 May 23.
A study was designed to recover Listeria monocytogenes from pasteurized milk and Minas frescal cheese (MFC) sampled at retail establishments (REs) and to identify the contamination source(s) of these products in the corresponding dairy processing plant. Fifty milk samples (9 brands) and 55 MFC samples (10 brands) were tested from REs located in Juiz de Fora, Minas Gerais, Brazil. All milk samples and 45 samples from 9 of 10 MFC brands tested negative for L. monocytogenes; however, "brand F" of MFC obtained from REs 119 and 159 tested positive. Thus, the farm/plant that produced brand F MFC was sampled; all samples from the milking parlor tested negative for L. monocytogenes, whereas several sites within the processing plant and the MFC samples tested positive. All 344 isolates recovered from retail MFC, plant F MFC, and plant F environmental samples were serotype 1/2a and displayed the same AscI or ApaI fingerprints. Since these results established that the storage coolers served as the contamination source of the MFC, plant F was closed so that corrective renovations could be made. Following renovation, samples from sites that previously tested positive for the pathogen were collected from the processing environment and from MFC on multiple visits; all tested negative for L. monocytogenes. In addition, on subsequent visits to REs 159 and 119, all MFC samples tested negative for the pathogen. Studies are ongoing to quantify the prevalence, levels, and types of L. monocytogenes in MFC and associated processing plants to lessen the likelihood of listeriosis in Brazil.
一项研究旨在从零售场所（REs）采集的巴氏杀菌牛奶和米纳斯弗雷斯科奶酪（MFC）中分离出单核细胞增生李斯特菌，并确定这些产品在相应乳制品加工厂中的污染源。从巴西米纳斯吉拉斯州茹伊斯迪福拉市的零售场所采集了50份牛奶样本（9个品牌）和55份MFC样本（10个品牌）进行检测。所有牛奶样本以及10个MFC品牌中9个品牌的45份样本单核细胞增生李斯特菌检测呈阴性；然而，从REs 119和159获得的MFC“品牌F”检测呈阳性。因此，对生产品牌F MFC的农场/工厂进行了采样；挤奶厅的所有样本单核细胞增生李斯特菌检测呈阴性，而加工厂内的几个地点以及MFC样本检测呈阳性。从零售MFC、工厂F的MFC和工厂F的环境样本中分离出的所有344株菌株均为血清型1/2a，并且显示出相同的AscI或ApaI指纹图谱。由于这些结果确定储存冷却器是MFC的污染源，工厂F被关闭以便进行整改翻新。翻新后，在多次访问中从加工环境和MFC中收集了先前病原体检测呈阳性地点的样本；所有样本单核细胞增生李斯特菌检测均为阴性。此外，在随后对REs 159和119的访问中，所有MFC样本该病原体检测均为阴性。目前正在进行研究，以量化MFC及相关加工厂中单核细胞增生李斯特菌的流行率、水平和类型，以降低巴西李斯特菌病的发生可能性。
