VOA慢速英语--美国卫生官员正在研究新冠加强疫苗

United States health experts are expected to recommend additional COVID-19 vaccine¹ shots for all Americans. The additional injection, called a booster, would be given eight months after a person received their second shot of the vaccine.

The goal of this move is to provide longer-lasting protection as the Delta² variant³ of the virus spreads across the country.

Federal health officials have been studying whether booster shots for the vaccinated⁴ would be needed as early as this autumn. They reviewed case numbers in the U.S. as well as the situation in other countries such as Israel. Early studies in Israel suggest the vaccine's protection against serious illness dropped among those vaccinated in January.

Two people who know about the matter talked with The Associated Press. They expect an announcement on the booster recommendation this week.

The U.S. Food and Drug Administration, or FDA, would have to officially approve the COVID-19 vaccines⁵ before additional injections could be given. At this time, the FDA has only given emergency approval for vaccines from Pfizer-BioNTech, Moderna and Johnson & Johnson. Full approval of the Pfizer shot is expected in the coming weeks.

Last week, U.S. health officials recommended boosters for some with weakened immune systems. The group includes people who have a higher risk of catching⁶ the virus such as cancer patients and organ transplant recipients⁷. Among them, there is evidence that vaccines provide less protection over time.

The director of the National Institutes of Health (NIH), Dr. Francis Collins, said Sunday the U.S. could decide in the coming weeks whether to offer booster shots to Americans this fall.

Among the first to receive them could be health care workers, older people and those in nursing homes. Because of their higher risk of catching the virus, they were some of the first Americans to be vaccinated last December.

Since then, the Centers for Disease Control and Prevention says, more than 198 million Americans have received at least one shot of a COVID-19 vaccine. Still, the U.S. is seeing a large increase of virus cases from the fast-spreading Delta variant in unvaccinated communities. The variant is also responsible for an increasing number of so-called "breakthrough infections" of fully⁸ vaccinated people.

Israel has one of the world's highest vaccination⁹ rates with the Pfizer shot. It is trying to control the increase of cases from the Delta variant by offering a booster shot to all people over 60. And European health officials said they are talking with vaccine developers about the need for boosters.

NIH head Collins said, "There is a concern that the vaccine may start to wane¹⁰ in its effectiveness." He noted¹¹ that the Delta variant is difficult to deal with. Collins continued, "The combination of those two means we may need boosters."

Health officials from the World Health Organization (WHO) have asked wealthier and more-vaccinated countries to delay the booster shots. They feel it would be better to give shots to unvaccinated people in the developing world.

Words in This Story

recommend – v. to say that someone or something is good and deserves to be chosen

variant – n. something that is different in some way from others of the same kind

immune system – n. the system that protects your body from diseases and infections

transplant – n. medical. to perform a medical operation in which an organ or other part that has been removed from the body of one person is put into the body of another person

nursing home – n. a place where people who are old or who are unable to take care of themselves can live and be taken care of

wane – n. to decrease in size, amount, length, or quality

1 vaccine   

n.牛痘苗，疫苗；adj.牛痘的，疫苗的

参考例句：

• The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
• She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

2 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。

3 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。

4 vaccinated   

[医]已接种的，种痘的，接种过疫菌的

参考例句：

• I was vaccinated against tetanus. 我接种了破伤风疫苗。
• Were you vaccinated against smallpox as a child? 你小时候打过天花疫苗吗？

5 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。

6 catching   

adj.易传染的，有魅力的，迷人的，接住

参考例句：

• There are those who think eczema is catching.有人就是认为湿疹会传染。
• Enthusiasm is very catching.热情非常富有感染力。

7 recipients   

adj.接受的；受领的；容纳的；愿意接受的n.收件人；接受者；受领者；接受器

参考例句：

• The recipients of the prizes had their names printed in the paper. 获奖者的姓名登在报上。 来自《简明英汉词典》
• The recipients of prizes had their names printed in the paper. 获奖者名单登在报上。 来自《现代英汉综合大词典》

8 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

9 vaccination   

n.接种疫苗，种痘

参考例句：

• Vaccination is a preventive against smallpox.种痘是预防天花的方法。
• Doctors suggest getting a tetanus vaccination every ten years.医生建议每十年注射一次破伤风疫苗。

10 wane   

n.衰微，亏缺，变弱；v.变小，亏缺，呈下弦

参考例句：

• The moon is on the wane.月亮渐亏。
• Her enthusiasm for him was beginning to wane.她对他的热情在开始减退。

11 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。