Listeria monocytogenes is a significant concern for the produce industry; however, there is limited information to support the practical decision-making to mitigate this risk. This study investigated the prevalence of Listeria spp. and L. monocytogenes in seven produce handling and processing (PHP) facilities in the Pacific Northwest. PHP facilities were defined as facilities that receive raw agricultural commodities and further handle, pack, wash, or process prior to distribution into the retail sector. Environmental swabs (n = 50/facility) were collected in high-risk areas (e.g., near raw product entry points) from seven PHP facilities over two visits. Listeria spp. were isolated using modified ISO 11290-1 method and speciated with Microgen® Listeria-ID. Listeria spp., including L. monocytogenes, were found in 5/7 PHP. Prevalence of Listeria spp. ranged from 2% to 26% in these five facilities. Drains, entry areas, and portable equipment consistently tested positive for Listeria spp. during active production. Two additional sampling rounds (n = 50/round) were conducted in the highest prevalence facility (Facility #1). Overall, Listeria spp. were detected in 44/150 (29.3%) swabs collected from Facility #1. This study demonstrated the high prevalence of Listeria spp. near raw product entry points across PHP facilities.

中文翻译：

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李斯特菌属的流行率。在太平洋西北部的农产品处理和加工设施中。

单核细胞增生李斯特菌是农产品行业的一个重要问题。然而，支持减轻这种风险的实际决策的信息有限。本研究调查了李斯特菌属的流行情况。和 L. monocytogenes 在太平洋西北部的七个农产品处理和加工 (PHP) 设施中。PHP 设施被定义为接收原始农产品并在分销到零售部门之前进一步处理、包装、清洗或加工的设施。在两次访问中，从七个 PHP 设施的高风险区域（例如，靠近生产品入口点）收集了环境拭子（n = 50/设施）。李斯特菌属 使用改进的 ISO 11290-1 方法分离，并用 Microgen® Listeria-ID 鉴定。在 5/7 PHP 中发现了李斯特菌，包括单核细胞增生李斯特菌。李斯特菌属的流行率。这五个设施的比例从 2% 到 26% 不等。下水道、入口区域和便携式设备的李斯特菌属持续检测呈阳性。在积极生产期间。在患病率最高的设施（设施#1）中进行了另外两轮抽样（n = 50/轮）。总体而言，李斯特菌属。在从设施 #1 收集的 44/150 (29.3%) 个拭子中检测到。这项研究表明李斯特菌属的高流行率。靠近 PHP 设施的原始产品入口点。这项研究表明李斯特菌属的高流行率。靠近 PHP 设施的原始产品入口点。这项研究表明李斯特菌属的高流行率。靠近 PHP 设施的原始产品入口点。