疫苗可以降低感染病毒（包括无症状感染）的概率，也可以减少病毒传播

李十三

数据显示，完全接种疫苗的人比未接种疫苗的人感染 SARS-CoV-2 的可能性更小。并且完全接种疫苗的人感染 Delta 变种比没有接种疫苗的人有较轻的临床症状。 尽管需要额外的研究，但接种疫苗的人感染 Delta 变体的传播率可能低于未接种疫苗的人。

data show fully vaccinated persons are less likely than unvaccinated persons to acquire SARS-CoV-2, and infections with the Delta variant in fully vaccinated persons are associated with less severe clinical outcomes. Infections with the Delta variant in vaccinated persons potentially have reduced transmissibility than infections in unvaccinated persons, although additional studies are needed.

https://www.cdc.gov/coronavirus/ ... cinated-people.html

李十三

来自美国和其他国家的多项研究表明，两次剂量的 COVID-19 mRNA 疫苗接种系列对由祖先和变异株引起的 SARS-CoV-2 感染（包括有症状和无症状感染）以及包括严重疾病在内的后遗症有效 ，住院，和死亡。

Multiple studies from the United States and other countries have demonstrated that a two-dose COVID-19 mRNA vaccination series is effective against SARS-CoV-2 infection (including both symptomatic and asymptomatic infections) caused by ancestral and variant strains and sequelae including severe disease, hospitalization, and death.

李十三

正如预期的那样，由于没有疫苗是 100% 有效的，因此在完全接种疫苗的人群中观察到了感染（例如突破性感染），尽管比未接种疫苗的人群中的感染率低得多； 疫苗对严重疾病的有效性仍然很高。

As expected, because no vaccines is 100% effective, infections in fully vaccinated persons (e.g. breakthrough infections) have been observed, albeit at much lower rates than infections among unvaccinated persons; vaccine effectiveness against severe disease remains high.

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结论

目前在美国批准或授权的 COVID-19 疫苗已被证明可以提供相当大的保护，防止由 COVID-19 引起的严重疾病和死亡。 这些发现以及早期证据表明感染了 SARS-CoV-2 的接种人群中病毒 mRNA 和可培养病毒水平降低，表明接种人群中任何相关的传播风险都显着降低：即使对于 Delta，证据表明完全接种了疫苗 被感染的人比未接种疫苗的人感染 Delta 的时间更短。

Conclusions

COVID-19 vaccines currently approved or authorized in the United States have been shown to provide considerable protection against severe disease and death caused by COVID-19. These findings, along with the early evidence for reduced levels of viral mRNA and culturable virus in vaccinated people who acquire SARS-CoV-2 infection, suggest that any associated transmission risk is substantially reduced in vaccinated people: even for Delta, evidence suggests fully vaccinated people who become infected are infectious for shorter periods of time than unvaccinated people infected with Delta.

李十三

一项对 Delta 传输的大规模分析来自英国 REACT-1 项目，该项目由伦敦帝国理工学院的一个团队领导，该项目每隔几周对超过 100,000 名英国志愿者进行测试。 该团队对 5 月、6 月和 7 月收到的样本进行了 Ct 分析，当时 Delta 正在迅速取代其他变体，成为该国 COVID-19 的主要驱动因素。 结果表明，在检测呈阳性的人中，接种疫苗的人平均病毒载量低于未接种疫苗的人。 帝国理工学院的流行病学家保罗·埃利奥特 (Paul Elliott) 说，这些结果与其他 Ct 研究不同，因为这项研究是随机抽样的，包括那些检测呈阳性但没有表现出症状的人。

One massive analysis of Delta transmission comes from the UK REACT-1 programme, led by a team at Imperial College London, which tests more than 100,000 UK volunteers every few weeks. The team ran Ct analyses for samples received in May, June and July, when Delta was rapidly replacing other variants to become the dominant driver of COVID-19 in the country. The results suggested that among people testing positive, those who had been vaccinated had a lower viral load on average than did unvaccinated people. Paul Elliott, an epidemiologist at Imperial, says that these results differ from other Ct studies because this study sampled the population at random and included people who tested positive without showing symptoms.

https://www.nature.com/articles/d41586-021-02187-1

粤式油鸡

我记得之前有个报道说，接种的相对未接种的人，原始毒株病毒栽量减少，但delta的病毒栽量不变。可能我记错了。

李十三

粤式油鸡 发表于 2021-9-21 17:10
我记得之前有个报道说，接种的相对未接种的人，原始毒株病毒栽量减少，但delta的病毒栽量不变。可能我记错 ...

建议看5#提供的链接。里面有提到经常被引用的关于病毒载量的研究。

李十三

目前在澳大利亚使用的 COVID-19 疫苗可有效降低已接种疫苗的人在感染后将病毒传播给密切接触者的可能性。

The COVID-19 vaccines currently used in Australia is effective in reducing the likelihood of a vaccinated person transmitting the virus to close contacts if the person is infected.

https://www.health.gov.au/sites/ ... id-19-vaccine_0.pdf

李十三

4 月，英格兰公共卫生部报告了一项针对 COVID-19 传播的大型研究的结果，该研究涉及 365,000 多个家庭，其中包括接种疫苗和未接种疫苗的成员。

它发现使用辉瑞或阿斯利康疫苗进行免疫可将病毒继续传播的机会降低 40-60%。 这意味着，如果有人在接种疫苗后被感染，与未接种疫苗的感染者相比，他们将感染传染给他人的可能性只有一半左右。

In April, Public Health England reported the results of a large study of COVID-19 transmission involving more than 365,000 households with a mix of vaccinated and unvaccinated members.

It found immunisation with either the Pfizer or AstraZeneca vaccine reduced the chance of onward virus transmission by 40–60%. This means that if someone became infected after being vaccinated, they were only around half as likely to pass their infection on to others compared to infected people who were not vaccinated.

https://www1.racgp.org.au/newsgp ... d-vaccines-do-reduc

李十三

以色列的一项研究在冠状病毒疫苗接种方面处于世界领先地位，它提供了一些关于这种减少传播背后的原因的线索。 研究人员在先前接种过疫苗的人群中发现了近 5000 例突破性感染病例，并确定了他们的鼻拭子中存在多少病毒。 与未接种疫苗的人相比，接种疫苗的人检测到的病毒量明显较低。

鼻子中的病毒越多，传染性越强，进一步传播的风险越大。

One study from Israel, which leads the world in coronavirus vaccinations, gives some clues about what is behind this reduced transmission. Researchers identified nearly 5000 cases of breakthrough infection in previously vaccinated people, and determined how much virus was present in their nose swabs. Compared to unvaccinated people, the amount of virus detected was significantly lower in those who got vaccinated.

More virus in the nose has been linked to greater infectiousness and increased risks of onward transmission.

https://www1.racgp.org.au/newsgp ... d-vaccines-do-reduc

李十三

最新数据显示，接种疫苗不仅可以保护接种疫苗的个人，还可以减少他们将病毒传播给他人的机会。

The latest data show that getting a shot not only protects vaccinated individuals, it reduces the chance they can spread the virus to others.

https://www.nationalgeographic.c ... mission-of-covid-19

李十三

将这两项研究放在一起，这意味着，对于每六个未接种疫苗的人感染的人，如果他们接种了疫苗，只有一个人会被感染。

Put these two studies together and it means that, for every six people that unvaccinated people infect, only one would have been infected had they had the jab.

https://www.theguardian.com/theo ... ly-to-pass-covid-on

李十三

除了对个体疫苗接种者的实质性保护外，2019 年冠状病毒病 (COVID-19) 疫苗可能会降低突破性感染的病毒载量，从而进一步抑制向前传播。

Beyond their substantial protection of individual vaccinees, coronavirus disease 2019 (COVID-19) vaccines might reduce viral load in breakthrough infection and thereby further suppress onward transmission.

https://www.nature.com/articles/s41591-021-01316-7

jingzheng2223

疫苗的作用应该是不再有太多争议了。除了身体原因还是打了比较保险

shanhengai

希望科普能夠传达到那些游行的建築工人

澳洲行

请谈谈副作用，谢谢

andysydney

seaweed82

新州7人病亡中3人已打2剂疫苗

希望打了疫苗的人注意防护

李十三

ren2000200

时间太短，需要继续长期观察

汪洋

之前的石棉也是这么介绍的，这好那好，现在呢？别光说好处而回避副作用，人这一辈子长着呢

李十三

汪洋 发表于 2021-10-2 15:18
之前的石棉也是这么介绍的，这好那好，现在呢？别光说好处而回避副作用，人这一辈子长着呢 ...

一辈子有多长很难说。我说不定明天就挂了。

sampcheng

有多少效果

李十三

伦敦帝国学院的研究者们分析了随机从人群中抽取的10万多个鼻拭子，发现没打过疫苗的人Covid感染率比打过两针的人高3-4倍。

研究说完全接种能减少60%的感染机会 （不管有无症状的感染）。

https://www.oursteps.com.au/bbs/ ... 3098&mobile=yes