《自然》杂志中的奥密克戎节录
20220410
目录
1. 说明：
2. Heavily mutated Omicron variant puts scientists on alert
3. How severe are Omicron infections?
4. Beyond Omicron: what’s next for COVID’s viral evolution
5. How bad is Omicron? What scientists know so far
6. Omicron’s lasting mysteries: four questions scientists are racing to answer
7. Will Omicron end the pandemic? Here’s what experts say
8. Where did Omicron come from? Three key theories
9. Will Omicron finally overpower China’s COVID defences?
1.说明
文字节录自“Nature”，采用谷歌翻译译成中文，并将中英文一并列出。
2. Heavilymutated Omicron variant puts scientists on alert
nature news article NEWS 25 November 2021
“There’s a lot we don’t understand about this variant,” RichardLessells, an infectious-diseases physician at the University of KwaZulu-Natalin Durban, South Africa,said at a press briefing organized by South Africa’shealth department on 25 November. “The mutation profile gives us concern, butnow we need to do the work to understand the significance of this variant andwhat it means for the response to the pandemic.”
On 26November, the World Health Organization (WHO) designated the strain, known asB.1.1.529, as a variant of concern and named it Omicron, on the advice ofscientists who are part of the WHO’s Technical Advisory Group on SARS-CoV-2Virus Evolution. Omicron joins Delta, Alpha, Beta and Gamma on the current WHOlist of variants of concern.
“A burning question is ‘does it reduce vaccine effectiveness, becauseit has so many changes?’,” says Aris Katzourakis, who studies virus evolutionat the University of Oxford, UK. Moore says breakthrough infections have beenreported in South Africa among people who have received any of the three kindsof vaccines in use there, from Johnson & Johnson, Pfizer–BioNTech andOxford–AstraZeneca. Two quarantined travellers in Hong Kong who have testedpositive for the variant were vaccinated with the Pfizer jab, according to newsreports. One individual had travelled from South Africa; the other was infectedduring hotel quarantining.
Researchersin South Africa will also study whether B.1.1.529 causes disease that is moresevere or milder than that produced by other variants, Lessells said. “Thereally key question comes around disease severity.”
严重突变的 OMICRON 变体让科学家们保持警惕
nature news article NEWS 25 November 2021
11月25日，南非德班夸祖鲁纳塔尔大学的传染病医生理查德·莱塞尔斯在南非卫生部门组织的新闻发布会上说：“我们对这种变异有很多不了解的地方。”“突变谱让我们感到担忧，但现在我们需要开展工作以了解这种变体的重要性以及它对应对大流行病的意义。”
11月26日，根据世卫组织SARS技术咨询小组成员的科学家的建议，世界卫生组织(WHO)将该菌株称为B.1.1.529指定为关注的变种，并将其命名为Omicron-CoV-2病毒进化。Omicron与Delta、Alpha、Beta和Gamma一起出现在当前WHO关注的变体列表中。
英国牛津大学研究病毒进化的 Aris Katzourakis 说：“一个紧迫的问题是‘它是否会降低疫苗的有效性，因为它有很多变化？’”。摩尔说，南非已经报告了在接受强生、辉瑞-BioNTech和牛津-阿斯利康的三种疫苗中的任何一种的人中出现突破性感染。据新闻报道，两名在香港被隔离的旅客对该变异进行了阳性检测，他们接种了辉瑞疫苗。一个人从南非来过；另一人在酒店隔离期间被感染。
Lessells说，南非的研究人员还将研究B.1.1.529是否会导致比其他变体产生的疾病更严重或更轻微的疾病。“真正关键的问题在于疾病的严重程度。”
3.How severe are Omicron infections?
nature news article NEWS 17 December 2021
Ithas been less than four weeks since the announcement that a mutation-ladencoronavirus variant had been discovered in southern Africa. Since then, dozensof countries around the world have reported Omicron cases — including aworrying number of infections in people who have either been vaccinated orexperienced previous SARS-CoV-2 infections.
Thishas fuelled suggestions that Omicron causes milder disease than previousvariants. But researchers say it is too early to be sure, and keymethodological details of that study have not yet been published. Such detailsare crucial when interpreting data on disease severity, which can be confoundedby factors such as hospital capacity, the age and overall health of thoseinitially infected, and the extent of previous exposure to coronavirus.
Similarly,a 16 December report from Imperial College London found no evidence ofdiminished hospitalizations from Omicron infections compared with Delta inEngland, although this was again based on relatively few cases. Overall, thenumbers are still too small to draw firm conclusions about the severity ofdisease caused by Omicron, says Troels Lillebæk, an infectious-diseasespecialist at the University of Copenhagen.
Omicron 感染有多严重？
nature news article NEWS 17 December 2021
自从宣布在南部非洲发现了一种带有突变的冠状病毒变种以来，还不到四个星期。从那时起，全球数十个国家报告了Omicron病例，其中包括令人担忧的感染人数，这些人要么接种过疫苗，要么曾感染过SARS-CoV-2。
这促使人们认为Omicron导致的疾病比以前的变种更轻微。但研究人员表示，现在确定还为时过早，该研究的关键方法细节尚未公布。在解释疾病严重程度的数据时，这些细节至关重要，这些数据可能会受到医院容量、最初感染者的年龄和整体健康状况以及之前接触冠状病毒的程度等因素的混淆。
同样，伦敦帝国理工学院12月16日的一份报告发现，与英格兰的Delta相比，没有证据表明Omicron感染的住院人数有所减少，尽管这再次基于相对较少的病例。哥本哈根大学传染病专家Troels Lillebæk表示，总体而言，这些数字仍然太小，无法就Omicron引起的疾病的严重程度得出确切的结论。
4.Beyond Omicron: what’s next for COVID’s viral evolution
nature news feature article NEWS FEATURE 07 December 2021
“Now that we’ve had almost two years to see how SARS-CoV-2 evolves, Ithink there are clear parallels with 229E,” says Bloom. Variants such asOmicron and Delta carry mutations that blunt the potency of antibodies raisedagainst past versions of SARS-CoV-2. And the forces propelling this ‘antigenicchange’ are likely to grow stronger as most of the planet gains immunity to thevirus through infection, vaccination or both. Researchers are racing tocharacterize the highly mutated Omicron variant. But its rapid rise in SouthAfrica suggests that it has already found a way to dodge human immunity.
Scientistsare searching for ways to predict the virus’s next moves, looking to other pathogensfor clues. They are tracking the effects of the mutations in the variants thathave arisen so far, while watching out for new ones. They expect SARS-CoV-2eventually to evolve more predictably and become like other respiratory viruses— but when this shift will occur, and which infection it might resemble is notclear.
Otherestablished human viruses do not make the leaps in infectivity that SARS-CoV-2has in the past two years, and Bloom and other scientists expect the virus toeventually behave in the same way. Trevor Bedford, an evolutionary biologist atthe Fred Hutchinson, says the virus must balance its ability to replicate tohigh levels in people’s airways with the need to keep them healthy enough toinfect new hosts. “The virus doesn’t want to put someone in bed and make themsick enough that they’re not encountering a number of other people,” he says. Oneway for the virus to thread this needle would be to evolve to grow to lowerlevels in people’s airways, but maintain infections for a longer period oftime, increasing the number of new hosts exposed to the virus, says Rambaut.“Ultimately there’s going to be trade-off between how much virus you canproduce and how quickly you elicit the immune system.” By lying low, SARS-CoV-2could ensure its continued spread.
Ifthe virus evolved in this way, it might become less severe, but that outcome isfar from certain. “There’s this assumption that something more transmissiblebecomes less virulent. I don’t think that’s the position we should take,” saysBalloux. Variants including Alpha, Beta and Delta have been linked toheightened rates of hospitalization and death — potentially because they growto such high levels in people’s airways. The assertion that viruses evolve tobecome milder “is a bit of a myth”, says Rambaut. “The reality is far morecomplex.”
超越 OMICRON：SARS-COV-2进化的下一步是什么
nature news feature article NEWS FEATURE 07 December 2021
“现在我们已经有将近两年的时间来观察SARS-CoV-2是如何演变的，我认为与229E有明显的相似之处，”布鲁姆说。Omicron和Delta等变体携带的突变会削弱针对过去SARS-CoV-2版本产生的抗体的效力。随着地球上大部分地区通过感染、疫苗接种或两者兼而有之，获得对病毒的免疫力，推动这种“抗原变化”的力量可能会变得更强大。研究人员正在竞相描述高度突变的Omicron变体。但它在南非的迅速崛起表明它已经找到了一种躲避人类免疫力的方法。
科学家们正在寻找预测病毒下一步行动的方法，并从其他病原体中寻找线索。他们正在跟踪迄今为止出现的变体中突变的影响，同时注意新的变体。他们预计SARS-CoV-2最终会以更可预测的方式进化并变得像其他呼吸道病毒一样——但这种转变何时会发生，以及它可能类似于哪种感染尚不清楚。
其他已确定的人类病毒在传染性方面没有SARS-CoV-2在过去两年中的飞跃，布鲁姆和其他科学家预计该病毒最终会以同样的方式表现。Fred Hutchinson的进化生物学家Trevor Bedford说，该病毒必须平衡其在人类呼吸道中复制到高水平的能力与保持它们足够健康以感染新宿主的需要。“病毒不想让某人躺在床上，让他们病得很重，以至于他们不会遇到很多其他人，”他说。Rambaut说，病毒穿过这根针的一种方法是进化为在人的呼吸道中生长到较低水平，但会在较长时间内保持感染，从而增加暴露于病毒的新宿主的数量。“最终，你会在你能产生多少病毒和你激发免疫系统的速度之间做出权衡。”通过保持低调，SARS-CoV-2可以确保其继续传播。
如果病毒以这种方式进化，它可能会变得不那么严重，但结果还远未确定。“有这样一种假设，即更容易传播的东西会变得不那么致命。我不认为这是我们应该采取的立场，”Balloux说。包括Alpha、Beta和Delta在内的变异与住院率和死亡率升高有关-可能是因为它们在人们的呼吸道中增长到如此高的水平。Rambaut说，关于病毒进化为更温和的说法“有点神话”。“现实要复杂得多。”
5.How bad is Omicron? What scientists know so far
nature news article NEWS 02 December 2021
How fast is Omicron spreading?
Basedon the rise in COVID-19 cases and on sequencing data, Wenseleers estimates thatOmicron can infect three to six times as many people as Delta, over the sametime period. “That’s a huge advantage for the virus — but not for us,” he adds.
Can Omicron overcome immunity fromvaccines or infection?
Thevariant’s swift rise in South Africa hints that it has some capacity to evadeimmunity. Around one-quarter of South Africans are fully vaccinated, and it’slikely that a large fraction of the population was infected with SARS-CoV-2 inearlier waves, says Wenseleers, based on heightened death rates since the startof the pandemic.
Inthis context, Omicron’s success in southern Africa might be due largely to itscapacity to infect people who recovered from COVID-19 caused by Delta and othervariants, as well as those who’ve been vaccinated. A 2 December preprint1 fromresearchers at the NICD found that reinfections in South Africa have increasedas Omicron has spread. “Unfortunately, this is the perfect environment forimmune-escape variants to develop,” says Althaus.
Howwell the variant spreads elsewhere might depend on factors such as vaccinationand previous infection rates, says Aris Katzourakis, who researches viralevolution at the University of Oxford, UK. “If you throw it into the mix in ahighly vaccinated population that has given up on other control measures, itmight have the edge there.”
Does Omicron cause milder or more severedisease than previous variants?
Earlyreports linked Omicron with mild disease, raising hopes that the variant mightbe less severe than some of its predecessors. But these reports — which areoften based on anecdotes or scant scraps of data — can be misleading, cautionsMüge Çevik, an infectious-disease specialist at the University of St Andrews,UK. “Everyone is trying to find some data that could guide us,” she says. “Butit’s very difficult at the moment.”
Amajor challenge when assessing a variant’s severity is how to control for themany confounding variables that can influence the course of disease,particularly when outbreaks are geographically localized. For example, reports ofmild disease from Omicron infection in South Africa could reflect the fact thatthe country has a relatively young population, many of whom have already beenexposed to SARS-CoV-2.
Omicron有多糟糕？科学家到目前为止所知道的
naturenews article NEWS 02 December 2021
Omicron的传播速度有多快？
根据COVID-19病例的增加和测序数据，Wenseleers估计Omicron在同一时期内感染的人数是Delta的三到六倍。“这对病毒来说是一个巨大的优势-但对我们来说不是，”他补充道。
Omicron能否克服疫苗或感染的免疫力？
该变种在南非的迅速崛起暗示它具有一定的逃避免疫力的能力。Wenseleers说，根据自大流行开始以来的死亡率上升，大约四分之一的南非人已完全接种疫苗，而且很可能有很大一部分人口在较早的浪潮中感染了SARS-CoV-2。
在这种情况下，Omicron在南部非洲的成功可能主要是由于它能够感染由Delta和其他变体引起的从COVID-19中康复的人，以及那些接种过疫苗的人。NICD研究人员12月2日的预印本1发现，随着Omicron的传播，南非的再感染人数有所增加。“不幸的是，这是免疫逃逸变体发展的完美环境，”Althaus说。
英国牛津大学研究病毒进化的 Aris Katzourakis 说，这种变异在其他地方的传播程度可能取决于疫苗接种和以前的感染率等因素。“如果你把它混入已经放弃其他控制措施的高度接种疫苗的人群中，它可能在那里具有优势。”
Omicron 是否会导致比以前的变种更轻微或更严重的疾病？
早期的报告将Omicron与轻度疾病联系起来，这引发了人们对这种变体可能没有其一些前辈那么严重的希望。但英国圣安德鲁斯大学传染病专家MügeÇevik警告说，这些报告——通常基于轶事或少量数据——可能会产生误导。“每个人都在努力寻找一些可以指导我们的数据，”她说。“但目前非常困难。”
评估变体严重程度的一个主要挑战是如何控制可能影响疾病进程的许多混杂变量，特别是当爆发在地理上是局部的时。例如，南非Omicron感染引起的轻度疾病报告可能反映了该国人口相对年轻的事实，其中许多人已经接触过SARS-CoV-2。
6.Omicron‘s lasting mysteries: four questions scientists are racing to answer
nature news feature article NEWS FEATURE 24 February 2022
Is it less severe? If so, why?
Hospitalizationand death rates for Omicron, compared with those for previous variants, seem tosuggest that it is a weaker strain. But because many people have some level ofimmunity, through COVID-19 vaccination or previous infection, it’s challengingto untangle how much of that reduced severity stems from people’s immunesystems being preconditioned to take on the virus, and how much from someinherent feature of the virus itself.
“It’s much more difficult to have a ‘clean’ genetic and immunologicalstudy,” says Jean-Laurent Casanova, a paediatric immunologist at theRockefeller University in New York City.
Omicron 的永恒之谜：科学家们竞相回答的四个问题
nature news feature article NEWS FEATURE 24 February 2022
是不是很严重？如果是这样，为什么？
与之前的变种相比，Omicron的住院率和死亡率似乎表明它是一种较弱的菌株。但是，由于许多人通过COVID-19疫苗接种或以前的感染而具有一定程度的免疫力，因此很难弄清楚这种降低的严重程度有多少是由于人们的免疫系统被预先准备好接受病毒，以及有多少是由于某些固有特征造成的。病毒本身。
“进行‘干净’的遗传和免疫学研究要困难得多，”纽约市洛克菲勒大学的儿科免疫学家 Jean-Laurent Casanova 说。
7.Will Omicron end the pandemic? Here’s what experts say
nature news article NEWS 31 January 2022
Althoughvaccines are likely to continue protecting against severe symptoms, Pagel says,infection will continue to spread. “I think the assumption is that none of thevaccines are going to give you long-lasting protection against infection,” shesays.
Tangagrees: “I don’t think vaccines are the way this pandemic is going to end.”
So,how will it end? Not with Omicron, researchers predict. “This will not be thelast variant, and so the next variant will have its own characteristics,”Medley says.
Thereare no guarantees that the next variant will be milder, but Tang says thatseems to be the pattern so far. “This virus is getting milder and milder witheach iteration,” he says.
Omicron会结束大流行吗？以下是专家的说法
nature news article NEWS 31 January 2022
Pagel说，尽管疫苗可能会继续预防严重症状，但感染将继续传播。“我认为假设是，没有一种疫苗可以为你提供持久的抗感染保护，”她说。
唐同意：“我不认为疫苗是这场大流行结束的方式。”
那么，结局会如何呢？研究人员预测，Omicron不会。“这不会是最后一个变体，因此下一个变体将有自己的特点，”Medley说。
不能保证下一个变种会更温和，但唐说这似乎是迄今为止的模式。“这种病毒每次迭代都变得越来越温和，”他说。
8.Where did Omicron come from? Three key theories
nature news feature article NEWS FEATURE 28 January 2022
Anothercurious feature of Omicron is that, from a genomic viewpoint, it consists ofthree distinct sublineages (called BA.1, BA.2 and BA.3) that all seem to haveemerged at around the same time — two of which have taken off globally. Thatmeans Omicron had time to diversify before scientists noticed it. Any theoryabout its origins has to take this feature into account, as well as the numberof mutations, notes Joel Wertheim, a molecular epidemiologist at the Universityof California, San Diego.
“The virus has to change to stick around,” says Ben Murrell, aninterdisciplinary virologist at the Karolinska Institute in Stockholm. Thereceptor-binding domain, where many of Omicron’s mutations are concentrated, isan easy target for antibodies, and probably comes under pressure to change in along-term infection.
Butnone of the viruses from individuals with chronic infections studied so far hashad the scale of mutations observed in Omicron. Achieving that would requirehigh rates of viral replication for a long time, which would presumably makethat person very unwell, says Rasmussen. “It seems like a lot of mutations forjust one person.”
Ifthis is the case, it means that the virus would have to replicate sufficientlyin a person’s body to explore the effects of combinations of mutations — whichwould take longer to achieve than if it were sampling the space of possiblemutations one by one.
And many scientists say they might never find out where Omicron came from. “Omicron really shows us the need for humility in thinking about our ability to understand the processes that are shaping the evolution of viruses like SARS-CoV-2,” says Bloom.
Omicron 是从哪里来的？三个关键理论
nature news feature article NEWS FEATURE 28 January 2022
Omicron的另一个奇怪特征是，从基因组的角度来看，它由三个不同的亚谱系（称为BA.1、BA.2和BA.3）组成，它们似乎都是在同一时间出现的——其中两个已经全球关闭。这意味着Omicron有时间在科学家注意到之前进行多样化。加州大学圣地亚哥分校的分子流行病学家Joel
Wertheim指出，任何关于其起源的理论都必须考虑到这一特征以及突变的数量。
“病毒必须改变才能继续存在，”斯德哥尔摩卡罗林斯卡研究所的跨学科病毒学家BenMurrell说。Omicron的许多突变集中的受体结合域是抗体的一个简单目标，并且可能在长期感染中面临改变的压力。
但迄今为止研究的慢性感染个体的病毒中没有一个具有在Omicron中观察到的突变规模。拉斯穆森说，要实现这一点，就需要长时间的高病毒复制率，这可能会使那个人非常不适。“对于一个人来说，似乎有很多突变。”
如果是这种情况，则意味着病毒必须在人体内充分复制才能探索突变组合的影响——这比逐个采样可能的突变空间需要更长的时间。
许多科学家表示，他们可能永远也找不到Omicron的来源。“Omicron确实向我们展示了在思考我们理解影响SARS-CoV-2等病毒进化过程的能力时需要保持谦逊，”布鲁姆说。
9.Will Omicron finally overpower China’s COVID defences?
nature news article NEWS 28 March 2022
All eyes are on China as it attempts to quash its largest COVID-19 outbreaks since the early days of the pandemic. More than 62,000 people across all 31 of its provinces are infected, most of them with the fast-spreading BA.2 Omicron variant.
If Omicron runs out of control, the effects could be devastating — and similar to the current outbreak in Hong Kong, where deaths have surged and hospitals are overwhelmed. An analysis by Airfinity, a life-sciences market analytics firm in London, suggests that more than one million people in mainland China could die during an Omicron wave, partly because of lower levels of protection in older people. Only 50% of people over the age of 80 are fully vaccinated, according to the Chinese government.
Recentexperience in Hong Kong has highlighted the cost of low vaccination rates inolder people. In early March, there were close to 900 cases of COVID-19 per100,000 residents in Hong Kong, the highest level recorded anywhere in theworld during the pandemic. Deaths have also surged to nearly 300 a day earlierthis month. Experts blame low vaccination rates in elderly people for theregion’s high mortality rate. Only about one-third of those aged over 80 yearsare fully vaccinated, and 90% of deaths have been in people who are not fullyvaccinated.
MainlandChina faces a similar predicament if the current outbreak is not controlled.China’s overall vaccination rate is higher than 85%. That has been achievedwith the introduction of a digital vaccination-passport system — required forentry into many public buildings and workplaces — and a colour-coded ‘healthcode’ that indicates whether someone poses an infection risk. But Cowling saysthat older people are less likely to use facilities that require a vaccinationpassport and have been able to remain unvaccinated.
Fifty-twomillion people aged over 60 years are yet to be fully vaccinated. The mostvulnerable — those aged over 80 years — are the least well vaccinated, withonly 20% having received the primary vaccination course and booster shot. Workby Cowling and his colleagues that is yet to be peer reviewed indicates thatthe Sinovac vaccine, one of the two main vaccines used in China, is effectiveat reducing severe cases and deaths, but that the third shot is necessary toconfer high levels of protection in those aged over 601.
Deathsfrom COVID-19 could be “much worse” than the 1 million estimated by Airfinityif Omicron spreads through the population, says Lu Jiahai, aninfectious-diseases epidemiologist at Sun Yat-sen University in Guangzhou,China. The government is “taking responsibility for people’s lives, so will notchange or relax the current prevention and control strategy”, he says.
Omicron最终会战胜中国的COVID防御吗？
naturenewsarticleNEWS28March2022
所有的目光都集中在中国，因为它试图遏制自大流行初期以来最大规模的COVID-19疫情。其所有31个省份的62,000多人受到感染，其中大多数人感染了快速传播的BA.2Omicron变体。
如果Omicron失控，其影响可能是毁灭性的——类似于目前在香港爆发的疫情，那里的死亡人数激增，医院人满为患。伦敦生命科学市场分析公司Airfinity的一项分析表明，中国大陆可能有超过100万人在Omicron浪潮中死亡，部分原因是老年人的保护水平较低。据中国政府称，只有50%的80岁以上的人接种了疫苗。
香港近期的经验凸显了老年人疫苗接种率低的成本。3月初，香港每100,000名居民中有近900例COVID-19病例，是大流行期间世界上任何地方的最高水平。本月早些时候，每天的死亡人数也飙升至近300人。专家将该地区的高死亡率归咎于老年人的低疫苗接种率。80岁以上的老年人中只有约三分之一完全接种了疫苗，90%的死亡发生在未完全接种疫苗的人群中。
如果当前的疫情得不到控制，中国大陆也将面临类似的困境。中国整体疫苗接种率高于85%。这是通过引入数字疫苗接种护照系统（进入许多公共建筑和工作场所所必需的）和一个颜色编码的“健康代码”来实现的，该系统指示某人是否存在感染风险。但考林说，老年人不太可能使用需要疫苗接种护照并且能够保持未接种疫苗的设施。
5200万60岁以上的人尚未完全接种疫苗。最脆弱的人——80岁以上的人——接种疫苗的效果最差，只有20%的人接受了初级疫苗接种课程和加强注射。Cowling及其同事尚未进行同行评审的工作表明，中国使用的两种主要疫苗之一科兴疫苗可有效减少重症病例和死亡人数，但第三次注射对于赋予高水平的为601岁以上的人提供保障。
中国广州中山大学传染病流行病学家卢家海说，如果Omicron在人群中传播，COVID-19造成的死亡人数可能比Airfinity估计的100万人“严重得多”。他说，政府“对人民生命负责，不会改变或放松当前的防控策略”。