Level 4 Reading 3A

Reading 3A

阅读3A

HOW SAFE IS OUR FOOD? The everyday activity of eating involves more risk than you might think. It is estimated that each year in the United States, 48 million people suffer from foodborne diseases; 128,000 of them are hospitalized, and 3,000 die. In the developing world, contaminated food and water kill over half a million children a year. In most cases, virulent types of bacteria are to blame. Bacteria are an integral part of a healthy life. There are 200 times as many bacteria in the intestines of a single human as there are human beings who have ever lived. Most of these bacteria help with digestion, making vitamins, shaping the immune system, and keeping us healthy. Nearly all raw food has bacteria in it as well. But the bacteria that produce foodborne illnesses are of a different, more dangerous kind. Bad Bacteria Many of the bacteria that produce foodborne illnesses are present in the intestines of the animals we raise for food. When a food animal containing dangerous bacteria is cut open during processing, bacteria inside can contaminate the meat. Fruits and vegetables can pick up dangerous bacteria if washed or watered with contaminated water. A single bacterium, given the right conditions, divides rapidly enough to produce billions over the course of a day. This means that even only lightly contaminated food can be dangerous. Bacteria can also hide and multiply on dishtowels, cutting boards, sinks, knives, and kitchen counters, where they're easily transferred to food or hands. Changes in the way in which farm animals are raised also affect the rate at which dangerous bacteria can spread. In the name of efficiency and economy, fish, cattle, and chickens are raised in giant "factory" farms, which confine large numbers of animals in tight spaces. Cattle, for example, are crowded together under such conditions that if only one animal is contaminated with the virulent bacteria E. coli O157:H7, it will likely spread to others. Tracking the Source Disease investigators, like Patricia Griffin, are working to find the sources of these outbreaks and prevent them in the future. Griffin, of the Centers for Disease Control and Prevention (CDC) in the United States, has worked in

我们的食物有多安全？ 日常饮食活动所涉及的风险比你想象的要大。 据估计，美国每年有4800万人患有食源性疾病； 其中128000人住院，3000人死亡。 在发展中国家，受污染的食物和水每年导致50多万儿童死亡。 在大多数情况下，致命的细菌是罪魁祸首。 细菌是健康生活不可或缺的一部分。 一个人的肠道里有200倍的细菌 因为有人类曾经生活过。 这些细菌大多有助于消化， 制造维生素，塑造免疫系统，保持我们的健康。 几乎所有的生食中都含有细菌。 但产生食源性疾病的细菌是另一种更危险的细菌。 坏细菌 许多产生食源性疾病的细菌存在于我们饲养的动物的肠道中。 当在加工过程中切开含有危险细菌的食用动物时， 里面的细菌会污染肉。 如果用受污染的水清洗或浇水，水果和蔬菜可能会感染危险的细菌。 在适当的条件下，一个细菌的分裂速度足以在一天内产生数十亿个细菌。 这意味着，即使是轻度污染的食物也可能是危险的。 细菌也可以在抹布、砧板、水槽、刀具和厨房柜台上隐藏和繁殖， 它们很容易转移到食物或手上。 农场动物饲养方式的变化也会影响危险细菌的传播速度。 以效率和经济的名义，鱼、牛和鸡在巨大的“工厂化”农场饲养， 这将大量动物限制在狭小的空间内。 例如，在这种情况下，牛会挤在一起 如果只有一只动物被毒力细菌大肠杆菌O157:H7污染， 它很可能会传播给其他人。 追踪来源 疾病研究人员，比如帕特里夏·格里芬， 正在努力寻找这些疫情的源头，并在未来加以预防。 美国疾病控制和预防中心（CDC）的格里芬曾在

the foodborne-disease business for 15 years. Periodic E. coli outbreaks turned her attention to the public food safety threat that exists in restaurants and in the food production system. Food safety is no longer just a question of handling food properly in the domestic kitchen. "Now," Griffin says, "we are more aware that the responsibility does not rest solely with the cook. We know that contamination often occurs early in the production process— at steps on the way from farm or field or fishing ground to market." Griffin's job is to look for trends in food-related illness through the analysis of outbreaks. Her team tries to identify both the food source of an outbreak and the contaminating bacteria. To link cases together, the scientists use a powerful tool called PulseNet, a national computer network of health laboratories that matches types of bacteria using DNA analysis. PulseNet allows scientists to associate an illness in California, say, with one in Texas, tying together what might otherwise appear as unrelated cases. Then it's the job of the investigators to determine what went wrong in the food's journey to the table. This helps them decide whether to recalls a particular food or to change the process by which it's produced. In January 2000, public health officials in the state of Virginia noted an unusual group of patients sick with food poisoning from salmonella. Using PulseNet, the CDC identified 79 patients in 13 states who were infected with the same type of salmonella bacteria. Fifteen had been hospitalized; two had died. What was the common factor? All had eaten mangoes during the previous November and December. The investigation led to a single large mango farm in Brazil, where it was discovered that mangoes were being washed in contaminated water containing a type of salmonella bacteria. Salmonella contamination is a widespread problem; salmonella cases involving contaminated chicken, melons, coconut, and cereals were reported in 2018. The mango outbreak had a larger lesson: We no longer eat only food that is in season or that is grown locally. Instead, we demand our strawberries, peaches, mangoes, and lettuce year-round. As a result, we are depending more and more on imports. Eating food grown elsewhere in the world means depending on the soil, water, and sanitary conditions in those places, and on the way in which their workers farm, harvest, process, and transport the food. Reducing the Risk There are a number of success stories that provide hope and show us how international food production need not mean increased risk of contamination. Costa Rica has made sanitary production of fruits and vegetables a nationwide priority. Fresh fruits and vegetables are packed carefully in sanitary conditions; frequent hand washing is compulsory; and proper toilets are provided for workers in the fields. Such changes have made Carmela Velazquez, a food scientist from the University of Costa Rica, optimistic about the future. "The farmers we've trained," she says, "will become models for all our growers." In Sweden, too, progress has been made in reducing the number of foodborne disease at an early stage. Swedish chicken farmers have eliminated salmonella from their farms by thoroughly cleaning the area where their chickens are kept, and by using chicken feed that has been heated to rid it of dangerous bacteria. Consequently, the chickens that Swedes buy are now salmonella-free. These successes suggest that it is indeed feasible for companies and farms to produce safe and sanitary food, while still making a profit.

从事食源性疾病业务15年。 周期性的大肠杆菌爆发使她将注意力转向了公共食品安全威胁 这存在于餐馆和食品生产系统中。 食品安全不再只是在家庭厨房里正确处理食物的问题。 “现在，”格里芬说， “我们更加意识到，责任不仅仅在于厨师。 我们知道污染通常发生在生产过程的早期-- 在从农场、田野或渔场到市场的路上。" 格里芬的工作是通过分析疫情来寻找与食品相关的疾病趋势。 她的团队试图确定疫情爆发的食物来源和污染细菌。 为了将病例联系在一起，科学家们使用了一种名为PulseNet的强大工具， 使用DNA分析匹配细菌类型的国家卫生实验室计算机网络。 PulseNet允许科学家将加利福尼亚州的一种疾病联系起来， 比如，德克萨斯州的一个案件，将原本可能看似无关的案件联系在一起。 然后，调查人员的工作是确定食物送到餐桌的过程中出了什么问题。 这有助于他们决定是召回特定的食物还是改变其生产过程。 2000年1月，弗吉尼亚州的公共卫生官员 注意到一组罕见的沙门氏菌食物中毒患者。 利用PulseNet，美国疾病控制与预防中心在13个州确定了79名感染同种沙门氏菌的患者。 15人住院；两人死亡。 共同因素是什么？ 去年11月和12月，所有人都吃过芒果。 调查在巴西发现了一个大型芒果农场， 在那里发现芒果是在含有一种沙门氏菌的污染水中清洗的。 沙门氏菌污染是一个普遍存在的问题； 2018年报告了涉及受污染鸡肉、甜瓜、椰子和谷物的沙门氏菌病例。 芒果疫情给了我们一个更大的教训： 我们不再只吃当季或当地种植的食物。 相反，我们全年都需要草莓、桃子、芒果和生菜。 因此，我们越来越依赖进口。 吃世界其他地方种植的食物意味着取决于这些地方的土壤、水和卫生条件， 以及他们的工人耕种、收割、加工和运输食物的方式。 降低风险 有许多成功的故事提供了希望 并向我们展示国际粮食生产不一定意味着污染风险增加。 哥斯达黎加已将水果和蔬菜的卫生生产作为全国优先事项。 新鲜水果和蔬菜在卫生条件下仔细包装； 经常洗手是强制性的；为田里的工人提供了合适的厕所。 这些变化使哥斯达黎加大学的食品科学家Carmela Velazquez对未来持乐观态度。 “我们培训的农民，”她说，“将成为我们所有种植者的榜样。” 在瑞典，在早期减少食源性疾病的数量方面也取得了进展。 瑞典养鸡户已经从农场中消除了沙门氏菌 彻底清洁饲养鸡的区域， 以及使用经过加热的鸡饲料来清除危险的细菌。 因此，瑞典人购买的鸡现在没有沙门氏菌。 这些成功表明，公司和农场生产安全卫生的食品确实是可行的， 同时仍然盈利。

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