VOA慢速英语2021--新研究显示奥密克戎在肺部繁殖的速度较慢

New Studies on Omicron: Variant¹ Multiplies at Slower Rate in Lungs

The Reuters news agency recently examined a group of new studies on COVID-19. These studies, for the most part, have yet to be closely examined by outside experts. They include information that needs further study to support their findings.

Omicron grows faster in airways³, slower in lungs

Researchers said last week that differences in how well Omicron and other variants⁴ of the coronavirus multiply may help predict Omicron's effects.

Compared to the earlier Delta⁵ variant, Omicron multiplies itself 70 times more quickly in tissues that line airway² passages. This may speed up person-to-person spread, the researchers said. But in lung tissues, Omicron multiplies 10 times more slowly than the original kind of the coronavirus. This difference might lead to less-severe illness.

An official report of these findings is under careful study by a group of experts before publication and has not been released by the research team. In a news release issued by Hong Kong University, study leader Dr. Michael Chan Chi-wai said, "It is important to note that the severity of disease in humans is not determined⁶ only by virus replication" but also by each person's immune response to the infection. Such a response sometimes turns into life-threatening inflammation.

Chan added, "By infecting many more people, a very infectious virus may cause more severe disease and death even though the virus itself may be less pathogenic."

Pathogenic is a term that describes something such as a type of bacteria or a virus that causes disease.

Chan explained further, "taken together with our recent studies showing that the Omicron variant can partially⁷ escape immunity⁸ from vaccines⁹ and past infection, the overall threat from Omicron variant is likely to be very significant."

Omicron holds cells more tightly, withstands some antibodies

Another group of researchers said a model of how the Omicron variant attaches to cells and antibodies gives information about its behavior and will help in designing treatments.

Using computer models of the spike¹⁰ protein on Omicron's surface, they examined changes occurring when the spike grabs onto a cell-surface protein called ACE2, the virus' way into the cell.

The research team also modeled the spike with different classes of antibodies trying to attack it. The antibodies attack from different places, "like a football team's defense¹¹ might tackle a ball carrier," said Joseph Lubin of Rutgers University in New Jersey¹².

The findings, posted last week on the website bioRxiv ahead of examination by outside experts, need to be checked, "particularly with real-world samples from people," Lubin said. He added "while our molecular¹³ structure predictions are by no means a final word on Omicron, (we hope) they enable a faster and more effective response from the global community."

Four in 10 infected people may unknowingly spread virus

A third study, put online last week in the publication JAMA Network Open, showed that infected people who show no symptoms might be helping¹⁴ to spread SARS-CoV-2, the virus that causes COVID-19. Such cases, known as asymptomatic cases, could make up to 40.5 percent of confirmed infections worldwide.

Researchers grouped data from 77 earlier studies involving a total of 19,884 individuals with confirmed SARS-CoV-2 infections. They found that among infected people in the general community, about 40 percent were asymptomatic, as were 54 percent of infected pregnant women, 53 percent of infected air or cruise travelers, 48 percent of infected nursing home residents or staff and 30 percent of infected healthcare workers or hospitalized patients.

The grouped percentage of asymptomatic infections was about 46 percent in North America, 44 percent in Europe and 28 percent in Asia.

Min Liu and other researchers at Peking University in China wrote "the high percentage of asymptomatic infections highlights" the possible spread risk of "asymptomatic infections in communities."

The researchers added that officials should check for asymptomatic infections, and those who are identified "should be under management similar to that for confirmed infections, including isolating¹⁵ and contact tracing."

Words in This Story

multiply – v. to increase greatly in number or amount : to become much more numerous

replication –- n. to repeat or copy (something) exactly

inflammation -- n. a response to cellular¹⁶ injury that serves as a mechanism¹⁷ to eliminate harmful agents and damaged tissue

significant -- adj. very important

model -- n. A system of data presented as a mathematical description of something

tackle -- v. to try to get the ball from (an opposing player who has it); American football or rugby : to force (the player with the ball) to fall to the ground

1 variant   

adj.不同的，变异的；n.变体，异体

参考例句：

• We give professional suggestions according to variant tanning stages for each customer.我们针对每位顾客不同的日晒阶段，提供强度适合的晒黑建议。
• In a variant of this approach,the tests are data- driven.这个方法的一个变种，是数据驱动的测试。

2 airway   

n.空中航线，通风口

参考例句：

• Lay them on their side and ensure the airway is unobstructed.让他们侧躺着，并确保呼吸道畅通。
• There is a purple airway in London Airport.伦敦机场里有一条皇家专用飞机跑道。

3 AIRWAYS   

航空公司

参考例句：

• The giant jets that increasingly dominate the world's airways. 越来越称雄于世界航线的巨型喷气机。
• At one point the company bought from Nippon Airways a 727 jet. 有一次公司从日本航空公司买了一架727型喷气机。

4 variants   

n.变体( variant的名词复数 )；变种；变型；（词等的）变体

参考例句：

• Those variants will be preserved in the'struggle for existence". 这些变异将在“生存竞争”中被保留下来。 来自辞典例句
• Like organisms, viruses have variants, generally called strains. 与其他生物一样，病毒也有变种，一般称之为株系。 来自辞典例句

5 delta   

n.（流的）角洲

参考例句：

• He has been to the delta of the Nile.他曾去过尼罗河三角洲。
• The Nile divides at its mouth and forms a delta.尼罗河在河口分岔，形成了一个三角洲。

6 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

7 partially   

adv.部分地，从某些方面讲

参考例句：

• The door was partially concealed by the drapes.门有一部分被门帘遮住了。
• The police managed to restore calm and the curfew was partially lifted.警方设法恢复了平静，宵禁部分解除。

8 immunity   

n.优惠；免除；豁免，豁免权

参考例句：

• The law gives public schools immunity from taxation.法律免除公立学校的纳税义务。
• He claims diplomatic immunity to avoid being arrested.他要求外交豁免以便避免被捕。

9 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

10 spike   

n.长钉，钉鞋；v.以大钉钉牢，使...失效

参考例句：

• The spike pierced the receipts and held them in order.那个钉子穿过那些收据并使之按顺序排列。
• They'll do anything to spike the guns of the opposition.他们会使出各种手段来挫败对手。

11 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

12 jersey   

n.运动衫

参考例句：

• He wears a cotton jersey when he plays football.他穿运动衫踢足球。
• They were dressed alike in blue jersey and knickers.他们穿着一致，都是蓝色的运动衫和灯笼短裤。

13 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

14 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。

15 isolating   

adj.孤立的，绝缘的v.使隔离( isolate的现在分词 )；将…剔出（以便看清和单独处理）；使（某物质、细胞等）分离；使离析

参考例句：

• Colour filters are not very effective in isolating narrow spectral bands. 一些滤色片不能很有效地分离狭窄的光谱带。 来自辞典例句
• This became known as the streak method for isolating bacteria. 这个方法以后就称为分离细菌的划线法。 来自辞典例句

16 cellular   

adj.移动的；细胞的，由细胞组成的

参考例句：

• She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
• Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

17 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。