为什么潜伏在绿叶蔬菜中的东西会让你生病

Why is lettuce so often the culprit in illness outbreaks linked to the bacteria E. coli?

为什么生菜总是大肠杆菌引发疾病的罪魁祸首?

A total of 121 people from 25 US states have become ill from E. coli contamination linked to romaine lettuce between March 13 and April 21, the US Centers for Disease Control and Prevention reported Wednesday. There has been one death in California resulting from an E. coli infection.

美国疾病控制与预防中心于本周三发布报告称，在3月13日至4月21日期间，美国25个州共有121人因（食用）生菜感染大肠杆菌而致病。加州有一人死于大肠杆菌感染。

E. coli can be found living in the intestines of both people and animals, as well as in food and in the environment. Almost all strains of E. coli are harmless, but some can cause stomach cramps, diarrhea and vomiting.

大肠杆菌既存在于人和动物的肠道内，也存在于食物和环境中。几乎所有的大肠杆菌都是无害的，但有些会引起胃痉挛、腹泻和呕吐。

Healthy adults usually recover from an infection of E. coli within a week, but some strains can cause more severe illness, especially in young children and older adults, who are at greater risk of developing kidney failure.

健康的成年人因大肠杆菌感染通常会在一周内恢复，但有些菌株会导致更严重的疾病，尤其是儿童和老年人，他们患肾衰竭的风险更大。

"Leafy greens, such as lettuce, can become contaminated in the field by soil, contaminated water, animals or improperly composted manure," said Jeff Farber, director of the Canadian Research Institute for Food Safety and a professor at University of Guelph in Ontario. "Lettuce can also be contaminated by bacteria during and after harvest from handling, storing and transporting the produce."

加拿大食品安全研究所所长、安大略省圭尔夫大学教授杰夫·法伯说:“生菜等绿叶蔬菜在地里可能会受到土壤、受污染的水、动物或不当堆肥的污染。”“生菜在处理、储存和运输过程中也会受到细菌污染。”

Usually, people eat romaine lettuce without cooking it, which could kill the germs. "Other raw fruits and vegetables that have come into contact with feces from infected animals are another common source of infection," Farber said.

通常情况下，人们吃生菜时不把它煮熟，而煮熟会杀死细菌。法伯说:“其他生的水果和蔬菜接触了受感染动物的粪便，这是另一个常见的感染源。”

Popularity also plays a role in why lettuce is a frequent bad actor: "Lettuce is also eaten the most out of all the produce items," he said.

受欢迎程度也影响了为什么生菜经常是一个坏角色:“在所有的农产品中，生菜也是吃得最多的，”他说。

From 2010 through the current outbreak, nine outbreaks have been caused by green lettuce or sprouts, compared with 12 from all other food groups, including meat, flour and prepared products, the CDC reports.

疾控中心的报告称，从2010年到目前的疫情爆发期间，绿色生菜或芽菜引发了九起疫情，而其他所有食品类别(包括肉类、面粉和加工食品)只有12起。

Many modes of contamination

多种污染方式

In the current outbreak, 52 of the 102 patients who have been interviewed by public health officials have been hospitalized, including 14 who developed a type of kidney failure called hemolytic uremic syndrome.

在目前的疫情中，公共卫生官员采访的102名患者中有52人住院，其中14人出现了一种被称为溶血性尿毒症综合征的肾衰竭。

Between 1998 and 2016, there were 45 outbreaks associated with E. coli in leafy vegetables reported in the United States, CDC spokeswoman Brittany Behm said. The new one is the largest outbreak of its kind since a deadly E. coli outbreak in 2006.

美国疾病控制与预防中心发言人布列塔尼贝母表示，1998年至2016年间，美国有45起与绿叶蔬菜中的大肠杆菌有关的疫情报告。这次新的疫情是自2006年致命的大肠杆菌爆发以来最大的一次。

In the new outbreak, the investigation revealed that several people in an Alaska correctional facility who became sick had consumed romaine lettuce sourced from Harrison Farms of Yuma, Arizona. The agency has not determined where in the supply chain contamination occurred.

在这次新爆发的疫情中，调查显示，在阿拉斯加的一所监狱中，有几名病人食用了亚利桑那州尤马市哈里森农场出产的生菜。该机构还没有确定在供应链的何处发生了污染。

"Lettuce can be contaminated in many different ways from the farm through the distribution chain," Behm said. "It could be from manure in the fields to contaminated water to contamination within a processing facility."

贝姆说:“从农场到配送环节，生菜可能受到很多不同方式的污染。“可能是田里的肥料，可能是被污染的水，也可能是加工设施里的污染物。”

She added that, although commercial producers do some testing for E. coli on wash water and irrigation water, not every single product that makes it into the hands of a customer is tested.

她补充说，尽管商业生产商在洗涤用水和灌溉用水上对大肠杆菌进行了一些检测，但并不是每一种进入消费者手中的产品都经过了检测。