美國疾病控制中心(Centers for Disease Control)和公共衛(wèi)生當(dāng)局有一個(gè)術(shù)語來描述新冠病毒突變:“令人擔(dān)憂的變異”。一種特殊的新冠變種正在讓他們感到不安。
它被稱為Delta變異。6月16日,美國疾病控制中心與世界衛(wèi)生組織(World Health Organization)一起確認(rèn)這種變異是一種“令人擔(dān)憂的”變異,它可能更易傳播,并導(dǎo)致更嚴(yán)重的疾病,這可能會(huì)對世界范圍內(nèi)的重新開放工作造成影響。
這種毒株也被稱為B.1.617.2冠狀病毒變種,最初在印度發(fā)現(xiàn),是在巴西、英國和其他地區(qū)發(fā)現(xiàn)的其他幾種地方性冠狀病毒毒株之一。但令衛(wèi)生官員擔(dān)憂的是,如果不采取遏制措施,這種病毒可能會(huì)蔓延至全球大部分地區(qū),成為主要病毒之一。由于Delta病毒變種的傳染性以及與之相關(guān)的疾病風(fēng)險(xiǎn)增加,英國在本周推遲了重新開放的計(jì)劃。Delta病毒變異占到了過去一周英國新發(fā)新冠肺炎病例的90%。
在美國,Delta變種的病例則要少得多,僅占新增感染病例的10%左右。不過在過去幾周,其傳播速度一直在上升。美國的病例數(shù)相對較低的一個(gè)原因,可能是該國正在進(jìn)行的積極的疫苗接種運(yùn)動(dòng)。在美國,迄今為止已經(jīng)有1.465億居民接種了完整的疫苗,超過總?cè)丝诘?4%。
這一變種的傳染性和嚴(yán)重性仍然困擾著醫(yī)學(xué)專業(yè)人士。格萊斯頓研究所(Gladstone Institutes)旗下的生物醫(yī)學(xué)所所長、內(nèi)科醫(yī)生迪帕克·斯里瓦斯塔瓦告訴美國廣播公司新聞(ABC News),在本周加州重新開放之前,應(yīng)當(dāng)密切關(guān)注這一變種的傳播。
早期證據(jù)表明,目前來自輝瑞(Pfizer)、Moderna和阿斯利康(AstraZeneca)的新冠疫苗對Delta變種提供了一些保護(hù)。社區(qū)內(nèi)接種疫苗的人越多,傳播風(fēng)險(xiǎn)就越低。
但是,根據(jù)目前的病例和住院情況,接種率低的社區(qū)應(yīng)當(dāng)必須繼續(xù)保持謹(jǐn)慎。專家指出,像這樣的變異的產(chǎn)生,正是人們不應(yīng)該只注射一劑或是兩劑新冠疫苗就“到此結(jié)束”的原因。
例如,英國的國家醫(yī)療服務(wù)體系(National Health Service)和英國大學(xué)的一項(xiàng)新研究發(fā)現(xiàn),兩劑阿斯利康和輝瑞的疫苗在預(yù)防感染Delta變體的患者住院治療方面的有效率分別為92%和96%。
Delta變體可能會(huì)在不同的地區(qū)產(chǎn)生不同的影響。比如,在年輕人免疫接種率較低的美國南方各州,隨著越來越多的人參加線下社交活動(dòng),以及口罩指令被取消,這種病毒可能會(huì)構(gòu)成威脅。
得克薩斯州兒童醫(yī)院疫苗開發(fā)中心(Center for Vaccine Development at Texas Children’s Hospital)的聯(lián)合主任彼得·霍特茲告訴美國消費(fèi)者新聞與商業(yè)頻道(CNBC):“在南方,特別是路易斯安那州和密西西比州,疫苗接種率非常低。在南方的許多州,只有不到10%的青少年接種了疫苗,所以這里真的很脆弱?!保ㄘ?cái)富中文網(wǎng))
編譯:楊二一
美國疾病控制中心(Centers for Disease Control)和公共衛(wèi)生當(dāng)局有一個(gè)術(shù)語來描述新冠病毒突變:“令人擔(dān)憂的變異”。一種特殊的新冠變種正在讓他們感到不安。
它被稱為Delta變異。6月16日,美國疾病控制中心與世界衛(wèi)生組織(World Health Organization)一起確認(rèn)這種變異是一種“令人擔(dān)憂的”變異,它可能更易傳播,并導(dǎo)致更嚴(yán)重的疾病,這可能會(huì)對世界范圍內(nèi)的重新開放工作造成影響。
這種毒株也被稱為B.1.617.2冠狀病毒變種,最初在印度發(fā)現(xiàn),是在巴西、英國和其他地區(qū)發(fā)現(xiàn)的其他幾種地方性冠狀病毒毒株之一。但令衛(wèi)生官員擔(dān)憂的是,如果不采取遏制措施,這種病毒可能會(huì)蔓延至全球大部分地區(qū),成為主要病毒之一。由于Delta病毒變種的傳染性以及與之相關(guān)的疾病風(fēng)險(xiǎn)增加,英國在本周推遲了重新開放的計(jì)劃。Delta病毒變異占到了過去一周英國新發(fā)新冠肺炎病例的90%。
在美國,Delta變種的病例則要少得多,僅占新增感染病例的10%左右。不過在過去幾周,其傳播速度一直在上升。美國的病例數(shù)相對較低的一個(gè)原因,可能是該國正在進(jìn)行的積極的疫苗接種運(yùn)動(dòng)。在美國,迄今為止已經(jīng)有1.465億居民接種了完整的疫苗,超過總?cè)丝诘?4%。
這一變種的傳染性和嚴(yán)重性仍然困擾著醫(yī)學(xué)專業(yè)人士。格萊斯頓研究所(Gladstone Institutes)旗下的生物醫(yī)學(xué)所所長、內(nèi)科醫(yī)生迪帕克·斯里瓦斯塔瓦告訴美國廣播公司新聞(ABC News),在本周加州重新開放之前,應(yīng)當(dāng)密切關(guān)注這一變種的傳播。
早期證據(jù)表明,目前來自輝瑞(Pfizer)、Moderna和阿斯利康(AstraZeneca)的新冠疫苗對Delta變種提供了一些保護(hù)。社區(qū)內(nèi)接種疫苗的人越多,傳播風(fēng)險(xiǎn)就越低。
但是,根據(jù)目前的病例和住院情況,接種率低的社區(qū)應(yīng)當(dāng)必須繼續(xù)保持謹(jǐn)慎。專家指出,像這樣的變異的產(chǎn)生,正是人們不應(yīng)該只注射一劑或是兩劑新冠疫苗就“到此結(jié)束”的原因。
例如,英國的國家醫(yī)療服務(wù)體系(National Health Service)和英國大學(xué)的一項(xiàng)新研究發(fā)現(xiàn),兩劑阿斯利康和輝瑞的疫苗在預(yù)防感染Delta變體的患者住院治療方面的有效率分別為92%和96%。
Delta變體可能會(huì)在不同的地區(qū)產(chǎn)生不同的影響。比如,在年輕人免疫接種率較低的美國南方各州,隨著越來越多的人參加線下社交活動(dòng),以及口罩指令被取消,這種病毒可能會(huì)構(gòu)成威脅。
得克薩斯州兒童醫(yī)院疫苗開發(fā)中心(Center for Vaccine Development at Texas Children’s Hospital)的聯(lián)合主任彼得·霍特茲告訴美國消費(fèi)者新聞與商業(yè)頻道(CNBC):“在南方,特別是路易斯安那州和密西西比州,疫苗接種率非常低。在南方的許多州,只有不到10%的青少年接種了疫苗,所以這里真的很脆弱?!保ㄘ?cái)富中文網(wǎng))
編譯:楊二一
The Centers for Disease Control (CDC) and public health authorities have a term for worrisome mutations in viruses: “variants of concern.” And one particular COVID-19 variant now has officials on edge.
It’s called the Delta variant, and on June 16, the CDC joined the World Health Organization (WHO) in identifying this variant as one of “concern” that could be more transmissible and lead to more serious illness, throwing a potential wrench into worldwide reopening efforts.
This strain, also known as the B.1.617.2 coronavirus variant, was first identified in India and is one among several other local coronavirus strains that have been identified in Brazil, the U.K., and other regions. But what worries health officials is that the strain could become the dominant one throughout much of the world without containment efforts. The U.K. this week delayed its reopening plans owing to the transmissibility and increased risk of illness associated with the Delta variant, which accounted for 90% of new COVID-19 cases in the nation this past week.
In the U.S., the numbers for Delta variant cases are far lower, constituting about 10% of new infections, although the rate of spread has been increasing in the past few weeks. One reason for the relatively low case numbers that we know of to date may be the aggressive immunization campaign underway in the U.S., which has seen 146.5 million residents fully vaccinated to date, more than 44% of the overall population.
But this strain’s transmissibility and severity is giving some medical professionals pause. Deepak Srivastava, a physician and president of the Gladstone Institutes for biomedical research, told ABC News that it will be critical to keep an eye on this variant’s spread ahead of California’s reopening this week.
However, there has been early evidence that the current COVID-19 vaccines from Pfizer, Moderna, and AstraZeneca, offer some protection against the Delta variant, and the more people within a community who are vaccinated, the lower the risk of transmission.
But depending on cases and hospitalizations going forward caused by this pathogenic tweak, communities with low vaccination rates may have to continue being cautious. And experts point out that variants such as this are precisely why people shouldn’t get just one dose of a two-dose COVID vaccine and call it a day.
For instance, new research out of the U.K.’s National Health Service and British universities found that two doses of AstraZeneca’s or Pfizer’s vaccines were 92% or 96% effective, respectively, at preventing hospitalizations for patients who were infected by the Delta variant.
The Delta variant will likely have different effects in different regions. In Southern states with low immunization rates among young adults, for example, the strain could pose a threat as more and more people socialize in person and mask mandates are lifted.
“Here in the South, particularly in Louisiana, Mississippi, we’re seeing really low vaccination rates,” Peter Hotez, codirector of the Center for Vaccine Development at Texas Children’s Hospital, told CNBC. “And less than 10% of adolescents are vaccinated in many of these Southern states, so we have a real vulnerability here.”