Section outline

  • A healthcare professional administering a vaccine to a child's arm.

    Is giving shots to young children a good thing?
    ::给幼童打针是好事吗?

    Many, if not most, children hated going to the doctor, as it often meant getting a shot. Why? The shot actually contained a weakened or dead . And putting some of that dead pathogen into you was a good thing.
    ::许多,如果不是大多数,儿童都讨厌去看医生,因为这常常意味着要打一针。为什么?射击实际上包含一个虚弱或死亡。把一些死亡的病原体注入你身上是件好事。

    Immunity
    ::豁免豁免豁免

    Memory B and T cells help protect the body from re-infection by pathogens that infected the body in the past. Being able to resist a pathogen in this way is called immunity. Immunity can be active or passive.
    ::内存B和T细胞帮助保护身体免受过去感染身体的病原体的再次感染,能够以这种方式抵抗病原体被称为豁免,豁免可以是主动的,也可以是被动的。

    Active Immunity
    ::现行豁免

    Active immunity results when an immune response to a pathogen produces memory . As long as the memory cells survive, the pathogen will be unable to cause a serious infection in the body. Some memory cells last for a lifetime and confer permanent immunity.
    ::当对病原体的免疫反应产生内存时,可产生主动免疫效果。只要内存细胞存活下来,病原体将无法在身体中造成严重感染。有些内存细胞将持续一生,并给予永久免疫。

    Active immunity can also result from immunization . Immunization is the deliberate exposure of a person to a pathogen in order to provoke an immune response and the formation of memory cells specific to that pathogen. The pathogen is often injected. However, only part of a pathogen, a weakened form of the pathogen, or a dead pathogen is typically used. This causes an immune response without making the immunized person sick. This is how you most likely became immune to measles, mumps, and chicken pox. 
    ::免疫是指一个人故意接触病原体以引起免疫反应和形成该病原体特有的记忆细胞,而病原体往往被注射,但通常只使用病原体的一部分,病原体的衰弱形式,或死亡病原体。这造成免疫反应,而不使免疫人员生病。这就是你最有可能避免麻疹、流行性腮腺炎和水花。

    Passive Immunity
    ::被动豁免

    Passive immunity results when antibodies are transferred to a person who has never been exposed to the pathogen. Passive immunity lasts only as long as the antibodies survive in body fluids. This is usually between a few days and a few months. Passive immunity may be acquired by a fetus through its mother’s . It may also be acquired by an infant though the mother’s breast milk. Older children and adults can acquire passive immunity through the injection of antibodies.
    ::当抗体转移到从未接触过病原体的人身上时,将产生被动豁免的结果。 被动豁免只持续到抗体在体液中存活的时间。 被动豁免通常在几天到几个月之间。 胎儿可以通过母亲获得被动豁免。 婴儿也可以通过母亲的母乳获得被动豁免。 老年儿童和成年人可以通过注射抗体获得被动豁免。

      

     

    Further Reading
    ::继续阅读

    Summary
    ::摘要

    • Immunity is the ability to resist infection by a pathogen.
      ::豁免是指抵抗病原体感染的能力。
    • Active immunity results from an immune response to a pathogen and the formation of memory cells.
      ::对病原体的免疫反应和内存细胞的形成导致主动免疫。
    • Passive immunity results from the transfer of antibodies to a person who has not been exposed to the pathogen.
      ::向未接触病原体的人转移抗体后产生被动豁免。

    Review
    ::回顾

    1. What is immunity? What role do memory cells play in immunity?
      ::豁免是什么?记忆细胞在豁免中发挥什么作用?
    2. How is active immunity different from passive immunity? Why does active immunity last longer?
      ::主动豁免与被动豁免有何不同?为什么主动豁免持续时间更长?
    3. Explain how immunization prevents a disease such as measles, which is caused by a virus.
      ::说明免疫如何预防由病毒引起的麻疹等疾病。