近期在國內(nèi)引發(fā)新一波本土疫情的德爾塔毒株傳播速度更快，傳染性更強，引發(fā)了不少人的擔憂。新冠疫苗對變異株的有效性如何？為什么打過疫苗還會被感染？

在近日的國務院聯(lián)防聯(lián)控機制召開新聞發(fā)布會上，中國疾控中心研究員、科研攻關組疫苗研發(fā)專班專家組成員邵一鳴對此做出回應。

邵一鳴表示，

It is not surprising to see breakthrough infections－people who contract the virus at least 14 days after being fully vaccinated－because no vaccine is capable of totally preventing people from catching the virus.
完成疫苗接種至少14天后又被感染的病例被稱為“突破病例”，這并不是例外，因為沒有疫苗能夠百分之百防止人們感染病毒。

【知識點】

“突破病例”在英文報道中一般用breakthrough infections或者breakthrough cases表示，breakthrough做名詞的時候，我們最熟悉的意思是“（某個方面的）突破，重大進展”，比如：breakthrough in core technology（核心技術方面的突破），而在“突破病例”這個語境下，breakthrough其實是動詞短語break through的名詞形式，表示“the virus breaks through the protective barrier the vaccine provides”，即“病毒突破了疫苗產(chǎn)生的防護屏障”。

至于新冠疫苗對變異毒株的有效性，邵一鳴介紹：

"All COVID-19 vaccines around the world are evaluated based on their efficacy in preventing clinical disease, as well as their role in reducing serious cases and deaths," he said, adding that against these barometers, no marked difference has been found in domestic vaccines' effects on key mutations.
全球各條技術路線的疫苗有效性評估都是基于其在防止入院及減少重癥和死亡病例方面的效果，在這個評判標準下，國內(nèi)疫苗對幾個主要變異毒株的有效性并沒有顯著變化。

He added that an irrefutable benefit of vaccination lies in that it can always trigger robust "basic immunity" and protective memory cells in human bodies.
疫苗接種一個不可否認的益處在于，疫苗可以觸發(fā)強有力的“基礎免疫”并喚起人體內(nèi)的保護記憶細胞。

If immunity against the virus wanes in the long run, these memory cells can be "reawakened effectively" by delivering a booster shot and this will "produce very good protective effects", Shao said.
如果在比較長的時間后，身體對病毒的免疫能力逐漸下降，可以通過注射加強針重新喚起體內(nèi)的這些記憶細胞，并產(chǎn)生非常好的保護效果。

暫無全人群加強針接種必要

國際上有部分國家明確為民眾提供新冠疫苗加強針的接種，我國是否有考慮？對此，邵一鳴回應稱：

"For the general population who have been vaccinated within a year, there is no need to obtain a booster shot for now," he said.
對已完成免疫接種一年以內(nèi)的普通人群，暫無必要進行加強針接種。

【詞匯講解】

所謂疫苗加強針（booster shot/booster dose），是指在常規(guī)使用疫苗劑型、劑量注射后，額外增加的疫苗接種。這里的核心詞booster，來源于動詞boost，主要表示“加強、促進、推動”等意思，比如boost production（促生產(chǎn)），boost morale（提振士氣）等，在這里表示“increase or renew the effect of the vaccine”，即“增強疫苗產(chǎn)生的效果”。

Whether or not people with weak immune systems, such as the elderly and those suffering chronic illnesses, as well as workers at higher risk of contracting the virus or people planning to travel to high-risk areas need a booster dose six to 12 months after initial immunization, and when a booster shot should be rolled out are being researched.
對完成免疫超過6—12個月且免疫功能較弱的老年人和有基礎性疾病的患者，以及因工作需要去往高風險地區(qū)工作的人員等人群，是否有必要開展加強針，以及什么時間開展加強針的接種，正在進行研究。

疫苗接種必須和嚴格的防控措施并用

邵一鳴表示，

Many countries, despite their high vaccination coverage rates, are grappling with a resurgence of outbreaks due to a rush to relax anti-virus policies, such as wearing masks and maintaining social distancing.
雖然很多國家疫苗接種率已經(jīng)很高了，但是在放寬戴口罩和保持社交距離等疫情控制措施之后，仍然出現(xiàn)了大幅度的疫情反彈。

"This shows that inoculation must be used in conjunction with strict disease control measures," he said, calling on the public to continue practicing personal protective protocols.
這說明，疫苗接種必須和嚴格的防控措施并用，請大家繼續(xù)維持個人的防護措施。

【相關詞匯】

免疫屏障
immunity barrier

有效性和安全性研究
safety and efficacy research

常態(tài)化疫情防控
regular epidemic prevention and control

輸入病例
imported COVID-19 cases

本土病例
locally transmitted cases

無癥狀感染者
asymptomatic cases

傳染病檢疫及監(jiān)測
quarantining and monitoring of infectious diseases

流行病學調(diào)查
epidemiological investigation

集中觀察
concentrated observation

外防輸入、內(nèi)防反彈
to prevent the coronavirus from re-entering the country to cause a new epidemic

早發(fā)現(xiàn)、早報告、早隔離、早治療“四早”措施
the principle of early detection, reporting, quarantine and treatment

參考來源：北京日報、中國日報

（中國日報網(wǎng)英語點津 Helen）