概述

沙门菌感染(沙门菌病)是一种影响肠道的常见细菌性疾病。沙门菌通常生活在动物和人的肠道中,并通过粪便排出。人类最常经由被污染的水或食物而感染。

沙门菌感染患者一般没有症状。少数患者会在 8 到 72 小时内出现腹泻、发热和腹部绞痛。大多数健康人无需特殊治疗即可在几天之内康复。

在某些情况下,沙门菌感染引起的腹泻可能导致严重脱水,需要立即就医。如果感染扩散到肠道之外,还可能会引起危及生命的并发症。如果您到卫生条件糟糕的国家旅行,感染沙门菌的风险会更高。

症状

沙门菌感染通常是由于食用生的或未煮熟的肉类、禽肉、蛋或蛋制品造成的。疾病的潜伏期为几小时到两天。大部分沙门菌感染可以归为胃肠型流感(肠胃炎)。早期的体征和症状包括:

  • 恶心
  • 呕吐
  • 腹部绞痛
  • 腹泻
  • 发热
  • 寒战
  • 头痛
  • 大便带血

沙门菌感染的体征和症状一般会持续两到七天。腹泻最多可能会持续 10 天,然而有可能几个月后您的大便才能恢复正常。

少数种类的沙门菌会导致伤寒,这种疾病在发展中国家更为常见且有时会致命。

When to see a doctor

Most people don't need to seek medical attention for salmonella infection because it clears up on its own within a few days.

However, if the affected person is an infant, young child, older adult or someone with a weakened immune system, call a health care provider if illness:

  • Lasts more than a few days
  • Is associated with high fever or bloody stools
  • Appears to be causing dehydration, with signs such as such as urinating less than usual, dark-colored urine and having a dry mouth and tongue

病因

沙门菌生活在人、动物和鸟类的肠道内。大多数人因食用被粪便污染的食物而感染沙门菌。常见的受感染食物包括:

  • 生肉、家禽肉及海鲜。屠宰过程中粪便可能会沾到生肉和家禽肉上。从受污染的水中捕捞的海鲜可能会受到污染。
  • 生蛋。虽然蛋壳似乎是防止污染的完美屏障,但一些受感染的鸡在蛋壳形成之前就产下了含有沙门氏菌的鸡蛋。在自制蛋黄酱和荷兰辣酱时就会用到生蛋。
  • 水果和蔬菜。一些新鲜农产品,特别是进口品种,可能在田间浇水或在加工过程中使用被沙门氏菌污染的水清洗。厨房里也可能发生污染,例如生肉和家禽肉的汁液接触到未煮过的食物,如沙拉。

美国食品药物监督管理局还指出,一些沙门氏菌爆发的原因是香料中的污染物。该机构正在寻找提高香料安全性的方法。

如果准备食物的人上完厕所或换尿布后不洗手,许多食物都会受到污染。如果您接触了被污染的东西,包括宠物,尤其是鸟类和爬行动物,然后把手指放进嘴里,也会发生感染。

Infected food and water

Commonly infected foods include:

  • Raw meat, poultry and seafood. Feces may get onto raw meat and poultry during the butchering process. Seafood may be contaminated if harvested from contaminated water.
  • Raw or undercooked eggs. While an egg's shell may seem to be a perfect barrier to contamination, some infected chickens produce eggs that contain salmonella before the shell is even formed. Raw eggs are used in homemade versions of foods such as mayonnaise and hollandaise sauce.
  • Unpasteurized dairy products. Unpasteurized milk and milk products — sometimes called raw milk — may be contaminated with salmonella. The pasteurization process kills harmful bacteria, including salmonella.
  • Fruits and vegetables. Some fresh produce, particularly imported varieties, may be irrigated in the field or washed during processing with water contaminated with salmonella. Contamination can also occur in the kitchen, when juices from raw meat and poultry come into contact with uncooked foods, such as salads.

Improperly handled food

Many foods become contaminated when prepared by people who don't wash their hands thoroughly after using the toilet or changing a diaper or after handling contaminated food.

Infected surfaces

Infection can also occur if people touch something that is contaminated and then put their fingers in their mouths.

Infected pets and other animals

Animals and pets, especially birds and reptiles, may carry salmonella bacteria on their feathers, fur or skin or in their feces. Some pet foods may be contaminated with salmonella and can infect animals.

风险因素

有些因素可能导致您感染沙门菌的风险增加,包括可能让您近距离接触沙门菌的活动以及可能削弱您对整体感染抵抗力的健康问题。

接触增加

  • 国际旅行。沙门菌感染(包括引起伤寒的种类)在卫生条件差的发展中国家更为常见。
  • 饲养宠物鸟或爬行动物。有些宠物,尤其是鸟类和爬行动物,可能携带沙门菌。

胃或肠道疾病

您的身体对沙门菌感染有很多天然防御能力。例如,强胃酸可以杀死很多类型的沙门菌。但有些疾病或药物可能导致这些天然防御能力失效。例如:

  • 抗酸剂。降低胃部酸度会让更多沙门菌存活下来。
  • 炎性肠病。这种疾病会损伤肠道内膜,使沙门菌更容易滋生。
  • 最近使用过抗生素。这可能导致肠道中的“有益”细菌减少,进而削弱您抵御沙门菌感染的能力。

免疫问题

以下疾病或药物可能会削弱您的免疫系统,从而导致您感染沙门菌的风险增加。

  • AIDS
  • 镰状细胞病
  • 疟疾
  • 器官移植后使用的抗排斥药物
  • 皮质类固醇

Increased exposure

  • International travel. Salmonella infection, including varieties that cause typhoid fever, is more common in developing countries with poor sanitation.
  • Owning, handling or petting animals. Some animals, particularly birds and reptiles, can carry salmonella bacteria. Salmonella can also be found in animal pens, tanks, cages and litter boxes.

Stomach or bowel disorders

The body has many natural defenses against salmonella infection. For example, strong stomach acid can kill many types of salmonella bacteria. But some medical problems or medications can short-circuit these natural defenses.

Examples include:

  • Antacids. Lowering the stomach's acidity allows more salmonella bacteria to survive.
  • Inflammatory bowel disease. This disorder damages the lining of your intestines, which makes it easier for salmonella bacteria to take hold.
  • Recent use of antibiotics. This can reduce the number of "good" bacteria in your intestines, which may impair your ability to fight off a salmonella infection.

Immune problems

Some medical problems or medications appear to increase your risk of catching salmonella by weakening your immune system. This interferes with your body's ability to fight infection and disease. Examples include:

  • HIV/AIDS
  • Sickle cell disease
  • Malaria
  • Anti-rejection drugs taken after organ transplants
  • Corticosteroids

并发症

沙门菌感染通常不会威胁生命。但在某些人群中(尤其是婴幼儿、老年人、移植受者、孕妇和免疫功能低下人群,并发症的发展可能有危险性。

脱水

如果您不能喝足够的水来补充因持续腹泻而流失的体液,则可能脱水。警告信号包括:

  • 尿量减少
  • 口干舌燥
  • 眼睛凹陷
  • 分泌的泪液减少

菌血症

如果沙门菌感染进入您的血液(菌血症),则会感染整个身体组织,包括:

  • 大脑和脊髓周围的组织(脑膜炎)
  • 心脏或瓣膜的内膜(心内膜炎)
  • 骨骼或骨髓(骨髓炎)
  • 血管内膜,尤其是如果您做过血管移植

反应性关节炎

感染了沙门氏菌的人随后患上反应性关节炎的风险较大。反应性关节炎也称为赖特氏综合征,通常导致:

  • 眼睛刺激
  • 排尿疼痛
  • 关节疼痛

Dehydration

If you can't drink enough to replace the fluid you're losing from diarrhea, you may become dehydrated. Warning signs include:

  • Urinating less than usual or dark-colored urine
  • Dry mouth and tongue
  • Sunken eyes
  • No tears when crying
  • Being more tired than usual
  • Irritability or confusion

Bacteremia

If salmonella infection enters your bloodstream (bacteremia), it can infect tissues throughout your body, including:

  • The urinary system (urinary tract infection)
  • The tissues surrounding the brain and spinal cord (meningitis)
  • The lining of the heart or valves (endocarditis)
  • The bones or bone marrow (osteomyelitis)
  • The lining of blood vessels, especially if you've had a vascular graft, such as heart vessel bypass surgery

Reactive arthritis

People who have had salmonella are at higher risk of developing reactive arthritis from salmonella infection. Also known as Reiter's syndrome, reactive arthritis typically causes:

  • Eye irritation
  • Painful urination
  • Painful joints

预防

美国农业部出台了一项《沙门氏菌行动计划》,其中涉及更新家禽屠宰检查系统和加强对家禽和肉类的抽样和检测程序。该计划的目的是减少美国沙门菌感染的数量。

您还要注意避免将细菌传播给其他人。在准备食物或为婴儿、老年人和免疫系统减弱的人提供护理时,采取预防措施尤为重要。一定要彻底煮熟食物,并迅速冷藏或冷冻食物。

洗手

彻底洗净双手有助于防止沙门氏菌进入口腔或进入您制备的食物中。做完以下这些事后一定要洗手:

  • 上厕所
  • 换尿布
  • 处理生肉或家禽
  • 清理宠物粪便
  • 接触爬行动物或鸟类

物品分别存放

防止交叉污染:

  • 在冰箱中将肉类、家禽和海鲜与其他食物分开存放
  • 如有可能,在厨房中准备两块砧板,一块用来切生肉,另一块用来切水果和蔬菜
  • 不要将煮熟的食物放在盛放过生肉后没有清洗的盘子上

避免吃生蛋

饼干面团、自制冰激凌和蛋酒中都含有生蛋。如果必须食用生蛋,请确保这些蛋经过巴氏杀菌。

Wash your hands

Washing your hands thoroughly can help prevent the transfer of salmonella bacteria to your mouth or to any food you're preparing. Wash your hands with soap and water for 20 seconds after you:

  • Use the toilet
  • Change a diaper
  • Handle raw meat or poultry
  • Clean up pet feces
  • Touch pets or other animals and their habitats, especially reptiles or birds

Keep things separate

To prevent cross-contamination:

  • Store raw meat, poultry and seafood away from other foods in your refrigerator
  • If possible, have two cutting boards in your kitchen — one for raw meat and the other for fruits and vegetables
  • Never place cooked food on an unwashed plate that previously held raw meat
  • Wash food preparation surfaces thoroughly with soap and water

Avoid eating raw eggs

Homemade cookie dough, ice cream, mayonnaise, hollandaise sauce and eggnog all contain raw eggs. If you must consume raw eggs, make sure they've been pasteurized.

Cook and store food properly

Be sure to cook food thoroughly and refrigerate or freeze food promptly.

July 02, 2022
  1. Hohmann EL. Nontyphoidal salmonella: Gastrointestinal infection and carriage. http://www.uptodate.com/home. Accessed Nov. 21, 2016.
  2. Salmonella questions and answers: Food safety information. U.S. Department of Agriculture. http://www.fsis.usda.gov/wps/wcm/connect/abff4b65-494e-45f4-9d69-75e168c8524b/Salmonella_Questions_and_Answers.pdf?MOD=AJPERES. Accessed Nov. 21, 2016.
  3. Salmonella. Centers for Disease Control and Prevention. http://www.cdc.gov/salmonella/. Accessed Nov. 21, 2016.
  4. Oral rehydration therapy. http://www.uptodate.com/home. Accessed Nov. 21, 2016.
  5. Nontyphoidal salmonella infections. Merck Manual Professional Version. https://www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/nontyphoidal-salmonella-infections. Accessed Nov. 21, 2016.
  6. FSIS releases comprehensive strategy to reduce salmonella. U.S. Department of Agriculture Food Safety and Inspection Service. http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/foodborne-illness-and-disease/salmonella/sap. Accessed Nov. 21, 2016.
  7. FDA releases draft risk profile on pathogens and filth in spices, takes steps to strengthen spice safety. U.S. Food and Drug Administration. http://www.fda.gov/Food/NewsEvents/ConstituentUpdates/ucm372995.htm. Accessed Nov. 21, 2016.

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