Salmonella enterica Serovar Diversity, Distribution, and Prevalence in Public Access Waters from a Central California Coastal Leafy Green Growing Region during 2011 - 2016

Contaminated produce is responsible for nearly half of all foodborne illness, with leafy green vegetables causing more than any other produce type. An avenue of potential pre-harvest contamination is irrigation or surface water exposed to fecal contamination through contact with wildlife, livestock, and raw or poorly composted manure. Non-typhoidal Salmonella enterica is among the leading causes of bacterial foodborne illness and is estimated to be one of the highest burden foodborne pathogens worldwide. The species S. enterica is extremely diverse with six subspecies and over 2,500 different serovars, with approximately 100 serovars account for most human infections. The Central California Coastal region is an area of high agricultural productivity and is the largest produce-growing region in the United States. While the bulk of irrigation in this region is done with ground water, surface waters are available to wildlife and can flood farm fields during large rain events. From October 2011 to September 2016, we conducted an extensive survey of surface waters in this region for the prevalence of Salmonella. A preliminary report from the first two years of this survey reported on 996 isolates and indicated a Salmonella prevalence of 65%. The present report includes overall and seasonal prevalence data for the entire survey as well as the serovars and geographical distribution of Salmonella recovered from 1,941 individual isolates. This study is a contribution toward understanding of Salmonella ecology in the region.

污染的农产品几乎导致了所有食源性疾病的一半，其中叶状蔬菜的污染程度超过其他任何农产品类型。潜在的收获前污染途径包括灌溉或地表水，这些水源可能因野生动物、家畜以及未充分发酵或发酵不良的粪便的接触而受到粪便污染。非伤寒沙门氏菌（Non-typhoidal Salmonella enterica）是细菌性食源性疾病的主要病因之一，并估计是全球食源性病原体中负担最重的之一。沙门氏菌属（S. enterica）具有极高的多样性，包括六个亚种和超过2,500个不同的血清型，其中大约100个血清型导致了大部分的人类感染。中央加州海岸地区是一个农业生产力极高的区域，也是美国最大的农产品种植区。尽管该地区的大部分灌溉采用地下水，但地表水仍可供野生动物使用，并在大雨期间可能淹没农田。从2011年10月到2016年9月，我们对该地区的地表水进行了广泛的调查，以检测沙门氏菌的流行率。初步报告显示，在前两年的调查中发现了996个分离株，沙门氏菌的流行率为65%。本报告包含了整个调查的总体和季节性流行率数据，以及从1,941个个体分离株中恢复的沙门氏菌的血清型和地理分布。本研究旨在增进对该地区沙门氏菌生态学理解。