群体免疫究竟是怎么回事？
原创 庄建林 健康防护林
It's original, it's built, it's healthy, it's protected.
上个与英国提群体免疫策略的时候，正是一线防控没日没夜的时候，根本没时间来写，这几天群里讨论的热火朝天，决定还是写一些自己的看法。如有不当之处，敬请指教。
The last time I spoke with the United Kingdom about the group’s immunization strategy, there was no time to write when there was no day or night for a line of defense, and the heat of the days of discussion in the group decided to write its own opinion. If anything, please advise.
1.什么是herd immunity (群体免疫力)？
1. What is herd immunity?
在一个特定人群中，拥有对某种传染病免疫力的人群的比例（%，百分比），称为群体免疫力。
Within a specific population group, the proportion of the population with immunity from a certain infectious disease (%, percentage) is referred to as group immunity.
有别于个体的免疫力，这种群体中有免疫力的人群对同一人群中无免疫力人群的间接保护被定义为群体保护效应(herd effect)。
Unlike individual immunity, the indirect protection of the immunised population in this group against the immunised population in the same group is defined as the protective effect of the group (herd effect).
通俗地说，就是一群人的大部分都有免疫力，即使发生了传染病，传播的范围也很有限，不容易形成暴发，即使有小部分人没有免疫力，也因为接触概率的问题不会被传染，从而也被“保护”起来。
It is commonplace to say that a large part of a group of people is immune, that, even when infectious diseases occur, their spread is limited and does not easily lead to outbreaks, and that even if a small part of the population is immune, they are “protected” by the fact that the issue of probability of exposure is not contagious.
1
2.免疫力从哪里来？
2. Where does immunity come from?
（1） 宝宝从妈妈体内先天性获得的（持续时间不长，且你得确保妈妈体内有一定的抗体水平）；
(1) Progenitally acquired by the baby from the mother (for a short period of time, and you have to ensure that there is a certain antibody level in the mother);
（2） 自然感染（相当于“野生”的感染，抗体水平高，持续时间长，代价是不确定感染后是否能够活下来，以及各种并发症，后遗症）；
(ii) Natural infections (equivalent to “breeding” infections, high antibody levels, long duration at the cost of uncertainty as to whether the infection will survive, as well as complications, after-effects);
（3） 疫苗（相当于“人工养殖”的感染，通常获得的抗体水平不如自然感染那么高且持久，但一般也达到保护水平；目前对付传染病普遍使用的方法，虽然有极少部分人发生接种后不良反应，但是从群体角度测算比自然感染的危害要低的多）；
(3) Vaccines (the level of antibodies generally obtained is not as high and sustainable as the level of natural infections, but generally the level of protection; the methods currently used to deal with infectious diseases are much lower than the harm of natural infections from a group perspective, although very few people suffer adverse post-inoculation effects);
（4） 注射免疫球蛋白（相当于直接补充进人体的，短平快，但不适合大规模使用）等。
(4) Injection of immunoglobin (equivalent to direct addition to the human body, short and flat, but not suitable for large-scale use), etc.
这四种情况中，疫苗无非是构建群体免疫力比较靠谱的手段。但前提是你得有足够安全有效的疫苗。
In all four cases, vaccines are a more reliable means of building group immunity. But only if you have enough safe and effective vaccines.
2
3.群体免疫力要多高才能阻止新冠病毒流行？
3. How much mass immunity is needed to stop the new coronary virus epidemic?
还记得R0吗？基本传播数，就是在自然情况下，一个传染病患者平均可以传染的人数。很显然，R0越高，传播力越强，要构建的群体免疫力比例就要越高。初步的计算公式见下图。
Remember R0? Basic transmission is the average number of people who are infected with an infectious disease in natural situations. Obviously, the higher R0 is, the more powerful it is, the higher it is for the group to be immune.
3
4.我们现在能实施群体免疫策略吗？
4. Can we now implement a group immunization strategy?
有朋友问我，现在我们国家的人大部分没有免疫力，等国外感染的差不多了，那我们就危险了。那么，我们能实施群体免疫策略吗？
A friend asked me if most people in our country are immune now, and when we get infected abroad, we're in danger. So, can we implement a group immunization strategy?
我们回去看问题2，现在实施群体免疫的时间还没有到来，因为方法3-疫苗还没有出来。方法1,4不考虑了，我们看方法2，理论上我们能不能通过精准划分人群（高危人群和非高危人群）自然感染的方法来构建人群免疫屏障呢？
When we go back to question 2, the time has not yet come to implement group immunization, because method 3-vaccination is not yet available. If method 1-4 is not taken into account, let us look at method 2, can we in theory construct a population immune barrier by way of a precise classification of natural infections (both high-risk and non-high-risk populations)?
既然纸上谈兵，那么就简单推算一下我们国家自己的情况。
Now that we are talking on paper, let us simply deduce the situation of our country itself.
（1）我们假设2/3的群体免疫力可以阻断流行（不是阻断发病），假设50%无症状感染+40%轻症，居家或门诊治疗后康复+9%住院治疗后康复+1%死亡。这是把全人群拿来做分母计算，这1%死亡是什么概念呢？自己算一下（死亡人数=地区总人数*2/3*1%）。（备注目前全球病死率在5%左右。这边比例仅为参考使用，为虚拟比例）
(1) On the assumption that two-thirds of the group's immune capacity can stop the epidemic (not interrupt the outbreak), on the assumption that 50% of the unsymptomatic infections + 40% of minor disorders, rehabilitation after home or outpatient treatment + 9% of hospital treatment + 1% of deaths. This is a fraction of the whole population, what is the concept of 1% of deaths?
（2）我国2018年末60岁以上老年人口比例接近2.5亿人，占总人口约17.9%。在一些大城市，如上海，早已达到1/3左右。如果再把各种基础疾病（肥胖、高血压）等算上，高危人群的比例超过1/3了，怎么办，不够构建免疫屏障了…
(2) At the end of 2018, the proportion of older persons aged 60 years or over was close to 250 million, or 17.9 per cent of the total population, and in some major cities, such as Shanghai, it has already reached about a third. If basic diseases (obese, hypertension, etc.) are counted as more than a third of the population at high risk, what happens?
（3）我国的家庭结构三代同堂的不少，家庭聚集性传染是新冠聚集性发病的首要原因，所以你怎么阻断家庭内的传播（家里同时有高危和非高危人群）？
(3) There are three generations of family structures in the country, and where the concentrated transmission of sexually transmitted infections is the primary cause of the new conglomerate of sexually transmitted diseases, so how do you stop transmission within the family (there are also high-risk and non-high-risk groups in the home)?
（4）儿童虽然感染后以轻症为主，但我国儿科医生匮乏、资源紧缺是一个明显的问题，每年流感季节来临后去上海的几大儿科门诊排过队的家长就更有发言权了。
(4) Although children are mainly affected by mild illness after infection, the shortage of paediatricians and the scarcity of resources in our country is a clear problem, and parents who are in line at several major paediatric clinics in Shanghai every year after the onset of the flu season have had more say.
（5）9%住院率什么概念？即使我们假设这些人不住院，只是来医院配个药，5分钟一个人，就足以使现有的医疗资源崩溃。
What is the concept of (5) 9 per cent hospitalization? Even if we assume that these people are not hospitalized, just come to the hospital with a drug and a person in five minutes would be enough to collapse existing medical resources.
所以，希望通过自然感染达到群体免疫，目前来说，除非新冠病毒毒力发生重大变化，大幅削弱，致病力下降至类似于季节性流感一样，否则的话，疫苗就是构建群体免疫的必由之路。
Thus, in the hope of achieving mass immunization through natural infections, vaccines are now the necessary route to creating mass immunization unless the virulence of the new coronary virus is significantly reduced and the virulence is reduced to a level similar to seasonal influenza.
我国国家层面的血清流行病学调查已经在逐步部署实施中，接下来，我们可以通过湖北、湖北以外地区的人群感染情况来看看不同地区的人群免疫情况。
A sero-epidemiological survey at the national level has been gradually deployed, and we can then look at the immunization of populations in different regions through infection in areas beyond the north and the north of the lake.
4
5.国外实施的是群体免疫策略吗？
Is there a group immunization strategy in place abroad?
每个国家因地制宜地采取防控措施，由于个人获得的信息并不完整，所以不能妄下评论。至于防控效果，可以从WHO等发布的（新增、累计）确诊病例数、重症人数、死亡人数中自己比较一下。
Each country, depending on the local context, takes preventive measures, and because the information it receives is incomplete, it cannot comment on it. As for the preventive effect, it can be compared between the number of confirmed cases (new, cumulative) issued by WHO, the number of serious cases, and the number of deaths.
传统的传染病防控方法是控制传染源（病例隔离治疗）、切断传播途径（戴口罩、通风、洗手、保持社交距离）、保护易感人群（接种疫苗、预防性服药等）。其中并不包括自然感染。
Traditional methods of control and control of infectious diseases are control of the source of infection (segregated treatment of cases), cutting of transmission routes (face masks, ventilation, hand washing, maintaining social distance), protection of vulnerable populations (vaccination, preventive medication, etc.). Natural infections are not included.
没有疫苗，想要获得高水平免疫屏障，可以参考问题4。自己把各地区的人口总数代进去动手算一下。这就是一道小学2年级的数学题。
Without a vaccine, if you want to get a high level of immune barriers, you can refer to question 4.
在一些传染病，到底自然感染好和疫苗接种好的问题上，国外的一部分家长更倾向于自然感染，因为他们觉得“野生”的抗体更可靠。最典型的就是“水痘聚会 chickenpox party”，顾名思义，就是一个小朋友生水痘了，邀请其他小朋友来参加party，从而感染获得免疫力。
In some cases of infectious diseases, natural infections and vaccinations, some parents abroad prefer natural infections, because they feel that the antibodies of the “breeding” are more reliable. The most typical is “chickenpox party,” which, by definition, is a small friend who gives birth to a pox and invites other small friends to join the party, thereby infecting them with immunity.
可惜的是，新冠不是水痘，儿童期感染后痒两个礼拜大部分人就结束了，所以，这种方法是否适用心里就有数了。
Unfortunately, since the new crown is not a pox and most people end up itching two weeks after a childhood infection, the question of whether or not this method will be applied is well known.
6.对付新冠病毒肺炎，一定要疫苗吗？
6. Do you need a vaccine to deal with the new coronary virus pneumonia?
疫苗，或者特效药，有1个就可以。
Vaccines, or special effects, one can do it.
详见《新冠笔记11 我们能消灭新冠病毒吗？》。
For more details, New Crown Note 11, can we get rid of the new crown virus?
文章链接：https://mp.weixin.qq.com/s/icMDE2OZ1LY9GJVBZjVxEw
Articles link: https://mp.weixin.qq.com/s/icMDE2OZ1LY9GJVBjVxEw
6
7.新冠病毒是RNA病毒，容易变异怎么办？
What if the new coronary virus is RNA?
这个担心非常专业，RNA病毒确实比DNA病毒更容易发生变异。此前我们常见的流感病毒、诺如病毒等发生变异的速度就比较快。怎么办呢？
This fear is very professional, and the RNA virus is more likely to change than the DNA virus. The flu virus that we used to have, and the non-viral virus, have changed faster. What should we do?
首先，目前尚未监测到新冠病毒发生显著变异。
First, significant changes in the new coronary virus have not yet been monitored.
其次，如果新冠病毒产生类似流感病毒一样的变异，那就需要从免疫策略下手，把接种一次改为接种多次。
Secondly, if the new coronary virus produces a mutation similar to the influenza virus, it will need to move from an immunization strategy to a vaccination campaign.
再者，如果产生新的亚型，和其他疫苗的制备原理也是一样的，考虑多价疫苗。
Furthermore, if new sub-types are produced, the same rationale is applied to other vaccines, considering multi-priced vaccines.
前提：得先把能够预防目前流行株的疫苗研发出来。不能因为担心毒株变异就觉得目前的疫苗研发没有意义。
Precondition: A vaccine that can prevent the current strain must first be developed. Fear of a change in the strain does not make current vaccine development meaningless.
7
8.说来说去，群体免疫力对我们有什么用呢？
8. What is the use of group immunity for us?
当然有用啦~
Of course it works.
传染病不止新冠病毒肺炎一种，我们手头的成熟疫苗也有很多。对于小朋友，因为疫情导致的接种延迟，随着国内疫情的平稳，可以约起来、补起来了。
The epidemic is more than just a new coronary virus pneumonia, and we have a lot of mature vaccines at our disposal. For kids, because of the delays in vaccination caused by the epidemic, it can be met and replaced as the epidemic stabilizes in the country.
对于老年人，上海60岁以上户籍老年人的福利：免费的23价肺炎疫苗也可以考虑约起来、种起来了。
In the case of older persons, the welfare of older persons over 60 years of age in Shanghai: free 23-priced pneumonia vaccine can also be considered and grown.
成年人中，乙肝疫苗、麻疹-风疹-腮腺炎疫苗、流感疫苗、HPV疫苗、带状疱疹疫苗，等等等等，这些疫苗都有推荐接种人群，高危人群也可以考虑起来了。
Among adults, the hepatitis B vaccine, the measles-rubella-mumella vaccine, the influenza vaccine, the HPV vaccine, the herpe belt vaccine, etc., are recommended for vaccination and can be taken into account by populations at risk.
从广泛接种疫苗获得的可是靠谱的“群体免疫力”哦！
There's a lot of "group immunity" coming from a wide range of vaccinations.
【本文更新于2020年4月8日，随着疫情和研究的进展，知识点可能不断发生变化，请继续关注。本文图片来自于网络及标注之参考文献，非原创。】
[This paper was updated on April 8, 2020, and as the epidemic and research progresses, the knowledge points may change, so please remain focused. This picture is taken from the web and the annotated reference, not original.]
总顾问：姜庆五教授 医学顾问：长宁区疾控中心 赵文穗主任医师 蔡恩茂主任医师 汤泓副主任医师
General Counsel: Prof. Kang Kyung-woo, Medical Adviser: Dr. Jo Wen-ho, Director of the Changning District CDC, Dr. Choi En-moo, Deputy Director Tom.
IT技术支持：上海悦米信息技术有限公司 医学内容：庄建林名医工作室 编辑：张展 高慧
IT technical support: Shanghai Happiness Information Technology Co. Ltd. Medical content: Mansion Forest Clinic Editor: Zhang Xuan Goe-hyeok
*项目资助：本文受上海市科学技术委员会科普项目资助（项目编号：18dz2300700）
*Project funding: This document is funded by the Shanghai City Council for Science and Technology (SCSTC) project (project No. 18dz 23007000)
长宁区卫生和计划生育委员会公共卫生保障项目（2017年）
Public Health Security Project of the Health and Family Planning Committee of the Changning District (2017)
长宁区第四轮（2018-2020年）创新团队（后备）(基于人工智能和原创IP体系的传染病防控创新研发团队)
4th Round (2018-2020) Innovation Team (back-up) (Research and Development Team for Infectious Disease Control and Control based on Artificial Intelligence and the original IP System)
长宁区医学名专科：急性传染病防制科（学校急性传染病监测与防控）
Drangning District Medical Specialist: Acute Communicable Diseases Prevention Unit (According Communicable Disease Surveillance and Control in Schools)
原标题：《【新冠笔记-13】浅谈群体免疫》
Original title: Immunization of the Convergence Group.
注册有任何问题请添加 微信：MVIP619 拉你进入群
打开微信扫一扫
添加客服
进入交流群
1.本站遵循行业规范，任何转载的稿件都会明确标注作者和来源；2.本站的原创文章，请转载时务必注明文章作者和来源，不尊重原创的行为我们将追究责任；3.作者投稿可能会经我们编辑修改或补充。
