對于近日在一些國家出現(xiàn)的新冠病毒變異毒株奧密克戎，世界衛(wèi)生組織26日緊急召開專門評估會議，將其列為“需要關(guān)注”的變異毒株，要求各國加強監(jiān)測與測序工作。奧密克戎毒株為何“需要關(guān)注”？此次病毒突變的意義何在？現(xiàn)有防疫工具是否還有效？關(guān)于奧密克戎毒株你想知道的都在這里。

What is it called?
最新變異毒株叫什么？

The variant was initially referred to as B.1.1.529, but on Friday was designated as a variant of concern (VOC) by the World Health Organization because of its “concerning” mutations and because “preliminary evidence suggests an increased risk of reinfection with this variant”. The WHO system assigns such variants a Greek letter, to provide a non-stigmatising label that does not associate new variants with the location where they were first detected. The new variant has been called Omicron.
該變異毒株最初被稱為B.1.1.529，世界衛(wèi)生組織11月26日認定其為“需要關(guān)注”的變異株，因為其出現(xiàn)“令人擔憂”的突變以及“初步證據(jù)表明該變異株使人體再次感染的風險增加”。世衛(wèi)組織以希臘字母“奧密克戎”命名該變異毒株。這樣不帶歧視的命名形式確保這些新變異毒株的名字不會與它們首次被發(fā)現(xiàn)的地方關(guān)聯(lián)起來。

When was the Omicron variant first detected?
何時首次檢測到奧密克戎毒株？

The B.1.1.529 variant was identified on Tuesday and highlighted as a concern due to its high number of mutations, which could lead it to evade immunity. It was also linked to a surge in case numbers in the Gauteng province of South Africa, an urban area containing Pretoria and Johannesburg, in the past two weeks. These two factors put it quickly on the radar of international monitors, with the chief medical adviser to the UK Health and Security Agency describing the variant as the “most worrying we’ve seen”.
奧密克戎變異毒株于11月23日被發(fā)現(xiàn)，由于其存在大量突變，可能逃避人體的免疫系統(tǒng)，而引起關(guān)注。該變異株與過去兩周南非豪登?。ò壤胀永麃喓图s翰內(nèi)斯堡的城區(qū)）的病例數(shù)量激增有關(guān)。這兩個因素迅速引起了國際監(jiān)測機構(gòu)的注意，英國衛(wèi)生安全局首席醫(yī)學顧問稱這種變異毒株是“我們見過的最令人擔憂的”。

Where did it come from?
奧密克戎毒株從哪里來？

Although initially linked to Gauteng, the variant did not necessarily originate there. The earliest sample showing the variant was collected in Botswana on 11 November. Scientists say that the unusual constellation of mutations suggests it may have emerged during a chronic infection of an immunocompromised person, such as an untreated HIV/Aids patient.
雖然奧密克戎毒株最初與豪登省相關(guān)，但并不一定起源于豪登省。該變異株的最早樣本是11月11日在博茨瓦納收集到的?？茖W家稱，這種不尋常的大量突變表明，奧密克戎毒株可能是在免疫功能低下的人（如未經(jīng)治療的艾滋病病毒攜帶者或艾滋病患者）的慢性感染過程中出現(xiàn)的。

Why are scientists worried about it?
為什么科學家對此感到擔憂？

The variant has more than 30 mutations on its spike protein – the key used by the virus to unlock our body’s cells – more than double the number carried by Delta. Such a dramatic change has raised concerns that the antibodies from previous infections or vaccination may no longer be well matched.
奧密克戎毒株的刺突蛋白有30多個突變，是德爾塔毒株的兩倍多。刺突蛋白是病毒解鎖人體細胞的鑰匙。這種巨大的變化讓人擔心以前因感染或接種疫苗產(chǎn)生的抗體可能對奧密克戎毒株無效。

Is it more transmissible?
奧密克戎毒株傳播力更強嗎？

This is not yet clearcut but the emerging picture is worrying. There has been a surge of cases in South Africa from 273 cases on 16 November to more than 1,200 by the start of last week. More than 80% of these were from Gauteng province and preliminary analysis suggests the variant has rapidly become the dominant strain. The R value, which indicates how fast an epidemic is growing, is estimated to be 1.47 for South Africa as a whole, but 1.93 in Gauteng. There is a chance this is a statistical blip linked to a super-spreader event but the data has triggered enough concern for precautionary measures.
關(guān)于這點尚不清楚，但目前出現(xiàn)的情況令人擔憂。南非的病例從11月16日的273例激增到上周初的1200多例。其中80%以上來自豪登省，初步分析表明該變種已迅速成為優(yōu)勢菌株。R值表示流行病的傳播速度，據(jù)估算南非整體R值為1.47，豪登省R值為1.93。這可能是與超級傳播者有關(guān)的暫時性統(tǒng)計突變，但統(tǒng)計數(shù)據(jù)已經(jīng)足以讓人擔憂，需要采取預(yù)防措施。

Will existing vaccines work against it?
現(xiàn)有的疫苗對奧密克戎毒株有效嗎？

Scientists are concerned by the number of mutations and the fact some of them have already been linked to an ability to evade existing immune protection. These are theoretical predictions, though, and studies are rapidly being conducted to test how effectively antibodies neutralize the new variant. Real-world data on reinfection rates will also give a clearer indication on the extent of any change in immunity.
奧密克戎毒株基因突變的數(shù)量以及其中一些突變與逃避現(xiàn)有免疫保護的能力有關(guān)，這讓科學家感到擔憂。不過，這些都是理論上的預(yù)測，目前正在迅速開展研究，以測試抗體對新毒株的有效性如何。再感染率的真實數(shù)據(jù)也將更清楚地表明免疫力變化的程度。

Scientists do not expect that the variant will be entirely unrecognizable to existing antibodies, just that current vaccines may give less protection. So a crucial objective remains to increase vaccination rates, including third doses for at-risk groups.
科學家們并不認為現(xiàn)有抗體完全無法識別奧密克戎毒株，只是目前的疫苗保護力可能降低。因此，一個關(guān)鍵目標仍然是提高疫苗接種率，包括為高危人群提供第三劑疫苗。

What about existing drugs?
現(xiàn)有的藥物呢？

Scientists expect that recently approved antiviral drugs, such as Merck’s pill, will work as effectively against the new variant because these drugs do not target the spike protein – they work by stopping the virus from replicating. However, there is a bigger risk that monoclonal antibodies, such as Regeneron’s treatment, could fail or partially fail because they target parts of the virus that will have mutated.
科學家們預(yù)計，最近批準的抗病毒藥物，如默克的藥劑，將對這種新毒株同樣有效，因為這些藥物不針對刺突蛋白——它們通過阻止病毒復(fù)制發(fā)揮作用。然而，單克隆抗體（如再生元制藥公司的藥物）失敗或部分失敗的風險更大，因為它們針對的是病毒將發(fā)生突變的部分。

Will the variant cause more severe Covid?
感染奧密克戎毒株病情會更嚴重嗎？

There is no information yet on whether the variant leads to a change in Covid symptoms or severity – this is something South African scientists will be closely monitoring. Since there is a lag between infections and more serious illness, it will take several weeks before any clear data is available. At this stage, scientists say there is no strong reason to suspect that the latest variant will be either worse or milder.
目前還沒有關(guān)于該變異株是否會導(dǎo)致新冠病毒癥狀或嚴重程度改變的信息——南非科學家將密切關(guān)注這一點。由于感染和更嚴重的病癥之間存在時滯，因此需要幾周時間才能獲得明確的數(shù)據(jù)。在這個階段，科學家表示沒有強有力的理由懷疑感染奧密克戎毒株病情會更重或更輕。

來源：衛(wèi)報
編輯：董靜