Before you toss together a pre-rinsed bagged salad, you may want to give it another wash for good measure. Why? The spinach and lettuce inside could have some unwanted guests called李斯特菌。
李斯特菌，或李斯特菌，是一种在土壤，水和某些动物中发现的细菌。食用后，李斯特菌会引起一种称为李斯特氏病的食源性疾病，这是最严重的一种food poisoning。
即使您不熟悉李斯特菌，您也很可能在新闻中听说过食物召回。似乎每隔几周就有一次由于食物污染而再次召回。
虽然大多数李斯特菌对健康的成年人和儿童都不是问题，但据估计1,600人每年患李斯特氏病，大约有260人死亡。
您需要了解有关李斯特菌和李斯特菌感染的五件事。
1. Listeria is mysterious and an extremely resilient bacterium.
We now appreciate how much effort it takes to rid our world of disease-causing organisms, but listeria is strongly resistant to our efforts. Some say it’s as elusive as rats.
原因之一是因为它可以在寒冷的温度下增长，击败一种传统的食品安全防御：制冷。“华氏40度的制冷剂阻止了许多食源性细菌的生长，但并不会杀死大多数细菌。”Nathan Price, MD, a pediatric infectious disease specialist at Banner Health in Tucson, AZ. “Listeria is among the few bacteria that can actually multiply at refrigerated temperatures.”
2. Listeria can be dangerous (even life-threatening) for certain groups.
“Many people with a healthy immune system are able to fight off a listeria infection and most never even knew they had an infection because the symptoms were mild or non-existent,” said Dr. Price. “However, if you have a weakened immune system, listeriosis can lead to an increased risk of severe infection and death.”
对于老年人和患有免疫系统受损的患者，包括移植和癌症患者或与免疫相关的健康状况（例如HIV爱滋病and kidney disease, a listeria infection can be more serious. If you’re pregnant, listeriosis is10倍than the general population, and it can causemiscarriage，死产或早产。
“很多孕妇都完全没有症状,但是their baby can still get infected and can die before birth or have severe symptoms after they are born,” Dr. Price said. “They can also get a fever and have trouble breathing and become lethargic (tired). If they have an infection of the brain, this can lead to difficulty feeding, irritability and/or seizures.”
如果您有严重感染的高风险，那么如果您有症状，请务必寻求医疗服务。
3.诊断李斯特菌感染可能很困难。
“诊断李斯特氏病很困难，因为症状通常类似于其他感染influenza或影响肠道的病毒。”普莱斯博士说。
Symptoms can start right away, but sometimes it can take months for symptoms to show up after eating food contaminated with listeria. Symptoms may include fever, muscle aches, vomiting, diarrhea, headache and/or sore throat.
4. Listeria is primarily linked to dairy products, produce and prepackaged foods.
像您在新闻中看到的那样，李斯特菌爆发是由于受污染的食物而发生的。食物的烹饪和巴氏灭菌可以decrease the risk of infection，虽然制冷没有。
“Typical foods implicated in outbreaks include deli meats and unpasteurized milk, but outbreaks have occurred in冰淇淋，哈密瓜，豆芽和包装沙拉，”普赖斯博士说。“这是因为细菌在制备和包装过程中会污染这些食物。”
If you’re high risk for severe infection, the best way to avoid infection is to avoid high-risk foods. These include:
- 生奶和奶酪的生，未经糊涂的牛奶和软奶酪：Queso Fresco，Queso Blanco，Panela，Brie，Camembert，Feta
- 生芽：苜蓿，三叶草，萝卜，绿豆
- Hot dogs, pâté or meat spreads, lunch meats and cold cuts
- 冷藏烟熏海鲜：Nova风格，Lox，Kippered，熏制，生涩
- 瓜
- 未洗的原水果和蔬菜
5.您可以帮助预防李斯特氏病。
以下是一些重要的安全措施，以帮助保护您和您的家人免受引起李斯特菌病的细菌的影响：
- 吃巴氏杀菌的食物。When purchasing milk, yogurt, ice cream or cheese, make sure the label says, “Made with pasteurized milk.” When in doubt, skip it. After purchasing, make sure it is refrigerated at 40 degrees Fahrenheit or colder.
- 正确清洗和处理食物。在自来水和磨砂膏下冲洗原始农产品，例如瓜和黄瓜。总是将未煮过的肉类与蔬菜，熟食和读食食品分开。
- 保持厨房清洁。Wash hands, utensils, countertops and cutting boards after handling and preparing uncooked foods (this includes unwashed produce).
- Store lunch meats and cold cuts properly.商店打开的热狗包装不超过冰箱（未打开的包裹不超过两周）。在冰箱中，熟食店的开放式包装和切片不超过三到五天（不超过两周的时间工厂密封的未打开包）。
- Thoroughly cook meat.Use a meat thermometer to make sure meat, poultry and seafood reaches a safe minimum internal temperature.这是指南。如果您怀孕或高危人群，请在食用前加热热狗，冷切和熟食肉。
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