你可能听到与之相关的“牛群免疫力”一词新冠肺炎pandemic。
Some leaders — for example, Boris Johnson, the prime minister of the United Kingdom — suggested it might be a good way to stop or control the spread of the new coronavirus, known as SARS-CoV-2. Herd immunity is also called community immunity and herd or group protection.
Herd immunity happens when so many people in a community become免疫to an infectious disease that it stops the disease from spreading.
This can happen in two ways:
- 许多人在疾病和时间内合同疾病，对其进行免疫应答（自然免疫）。
- Many people arevaccinated针对疾病达到免疫力。
Herd immunity can work against the spread of some diseases. There are several reasons why it often works.
There are also many reasons why herd immunity won’t yet work to stop or slow the spread of SARS-CoV-2 or COVID-19, the disease caused by an infection of the new coronavirus.
当大量的人口变得对疾病的免疫时，这种疾病的蔓延减速或停止。
许多病毒和细菌感染从人蔓延到人。当大多数人没有得到或传播感染时，这种链条被打破了。
This helps protect people who aren’t vaccinated, or who have low functioning immune systems and may develop an infection more easily, such as:
For some diseases, herd immunity can go into effect when40 percentof the people in a population become immune to the disease, such as through vaccination. But in most cases,80％到95％of the population must be immune to the disease to stop its spread.
疾病越传播，群体中的免疫性百分比越高，才能实现畜群免疫力。季节性流感等疾病需要比麻疹更小的免疫人，这远远不可推动。
例如，每20人中有19人must have the麻疹vaccination for herd immunity to go into effect and stop the disease.
This means that if a child gets measles, everyone else in this population around them will most likely have been vaccinated, already have formed antibodies, and be immune to the disease to prevent it from spreading further.
畜群免疫的目标是防止他人收缩或传递导致感染性疾病如麻疹的胚芽。
然而，如果孩子周围有更多无人造成的麻疹，这种疾病可能会更容易传播，因为没有畜群免疫力。
To visualize this, picture someone without immunity as a red dot surrounded by yellow immune dots. If the red dot can’t connect to any other red dots, there’s herd immunity.
必须具有安全性缓慢或停止传染病的人的百分比称为“畜群免疫阈值”。
当您在收缩后对特定疾病的免疫发生时，发生自然免疫。这触发了您的免疫系统，使抗菌患有胚胎导致您内心的感染。抗体就像仅识别某些细菌的特殊保镖。
如果你再次暴露于胚芽，那么处理胚芽以前可以在它传播并使你生病之前攻击它的抗体。例如，如果你作为一个孩子的水痘，你最有可能再也不会得到它，即使你在与它的别人身边。
Natural immunitycan help create herd immunity, but it doesn’t work as well as vaccinations. There are several reasons for this:
- Everyone would have to develop the illness once to become immune.
- 发展疾病可能会有健康风险，有时会严重。
- 你可能不知道你是否有疾病，或者如果你免于它。
牛群免疫确实为某些疾病工作。挪威的人们成功为H1N1病毒而成功开发了至少部分畜群免疫力（猪流感) through vaccinations and natural immunity.
Similarly, in Norway, influenza was projected to cause fewer deaths in 2010 and 2011 because more of the population was immune to it.
Herd immunity can help stop the spread of illness, such as swine flu, and other outbreaks within an entire country. But it can change without anyone knowing. Also, it doesn’t always guarantee protection against any disease.
对于大多数健康的人来说，自然免疫从来都不是接种疫苗的替代品。
并非每种疾病都可以通过畜群免疫力阻止疫苗。例如，你可以得到破伤风from bacteria in your environment. You don’t get it from someone else, so herd immunity doesn’t work for this infection. Getting the vaccine is the only protection.
You can help build herd immunity to certain diseases in your community by making sure you and your family have up-to-date vaccinations. Herd immunity may not always protect every individual in the community, but it could help prevent widespread disease.
Masks, vaccinations, rapid testing prior to gatherings, physical distancing and frequent handwashing are the most reliable ways to help prevent you and those around you from contracting and potentially transmitting SARS-CoV-2, the virus that causes COVID-19.
There are several reasons why herd immunity isn’t the answer to stopping the spread of the new coronavirus:
- People who contract SARS-CoV-2 and develop COVID-19 can experience serious side effects. Severe cases can lead to death.
- Doctors don’t yet know exactly why some people who contract SARS-CoV-2 develop severe COVID-19, while others do not.
- Vulnerable members of society, such as older adults and people with some chronic health conditions, could get very sick if they’re exposed to this virus.
- 否则健康和年轻人可能会生病与covid-19。
- Hospitals and healthcare systems may be overburdened if many people develop COVID-19 at the same time.
Overall, herd immunity will likely never be achieved with COVID-19. The emergence of variants and the waning immunity after both vaccination and natural infection will mean populations across the globe will always be susceptible to a certain degree.
Outbreaks are likely to continue occurring. But the level of immunity present in a population will determine how bad the outbreak will be.
Almost all healthy adults, teens, and older children would need to be vaccinated to provide herd immunity for people who can’t get the vaccine or who are too ill to become naturally immune to it. This is even more true with the emergence of more infectious new variants like Delta and Omicron.
If you’re vaccinated and build immunity against SARS-CoV-2, you’re far less likely to contract the virus or transmit it. And if you do, the effects will be far less severe.
Herd immunity is community or group protection that happens when a critical number of the population is immune to a certain disease. It can help stop or slow the spread of an infectious disease like measles or swine flu.
All germs have ways to outwit and camouflage themselves from the immune system, and SARS-CoV-2 is no different.
The immunity obtained after one contracts SARS-CoV-2 is unreliable. The only type of immunity for this virus that you can count on being present is from a vaccine.
However both natural immunity (if present after infection) and vaccine-induced immunity have been shown to wane.
我们仍在学习如何打击这种传染性和快速变异的病毒。明确的是，畜群免疫不是Covid-19的有效解决方案。