Do I really need another booster? The answer depends on age, risk and timing

Do I really need another booster? The answer depends on age, risk and timing¹

　　Transcript²

　　The Biden administration has given the go-ahead for another COVID vaccine³ booster for people aged⁴ 50 and older and certain people who are immunocompromised. They can now get another Moderna or Pfizer-BioNTech booster at least four months after their last dose.

　　But just because you can get an additional booster, does that mean you need to?

　　Health officials argue that the protection provided by the COVID vaccine booster shots wanes⁵ over time. And they are concerned about people considered to be at highest risk of getting severe COVID.

　　But the Centers for Disease Control and Prevention didn't make it clear how urgently people should be lining⁷ up for second boosters. The agency says these groups are "eligible⁸" for the shots but it stopped short of saying they should get them. And some infectious disease experts say not everyone in this age group needs another shot now.

　　So, if you're wondering whether to get a second booster, here are a few key factors to consider.

　　Risk of serious illness increases with age

　　Risk tracks with age, and older people have the highest risk.

　　A recent study among people 60 and older in Israel found that rates of COVID-19 infection and serious illness were lower in people who had a fourth dose of the Pfizer vaccine compared to three shots.

　　"We're talking about extra protection from the most serious outcome of COVID," says Dr. Eric Topol, founder⁹ and director of the Scripps Research Translational Institute.

　　Dr. Bob Wachter, chair of the Department of Medicine at the University of California San Francisco, says he personally plans to sign up for a second booster.

　　"I'm 64 and pretty healthy," he says. "But the evidence is clear that six months out from my first booster shot, the effectiveness of that booster has waned¹⁰ considerably¹¹."

　　He says another dose will boost his immunity¹² and decrease the probability of infection. "The benefits are very real," Wachter says.

　　But for people under 60 it's less clear a second booster is necessary.

　　"I don't think we have the data for younger people, 50 to even 60," says Dr. Monica Gandhi, an infectious disease specialist at the University of California, San Francisco. The study out of Israel didn't include this younger age group.

　　She points out that other countries are targeting additional boosters for older people. Germany has authorized¹³ a fourth shot for people over 70. The U.K. is targeting people over the age of 75 and Sweden is giving fourth shots to people over 80. Gandhi says the U.S. "is jumping the gun" by forging ahead with shots for everyone over 50 without the relevant data.

　　Still the trendline is clear, says Dr. Peter Chin-Hong, an infectious disease specialist at UCSF.

　　"The older you are, the bigger the benefit," he says. Although the majority of deaths from COVID have been people older than 65, "there's a clear association with age and mortality with COVID," Chin-Hong says. "It's really, really striking and it starts at age 50."

　　His advice? "Walk to get the second booster if you're eligible." Then he says "walk a little faster the older you get." His mom is in her 80s and he wants to protect her as much as possible. "I'm telling her to walk quickly," he says.

　　Dr. Carlos del Rio, an infectious disease researcher at Emory University, thinks it's reasonable for people under 60 to wait. "The vaccines¹⁵ are holding up pretty well against severe disease and death," he says.

　　It's also worth noting that even for people over 60, the added protection of an additional booster shot is small in absolute terms. People who got the first booster already have a very low risk of dying from COVID. Chin-Hong points out that in the Israeli study less than .1% of people with a third shot died, a risk so low he calls it "remarkable¹⁶."

　　Among people who got the fourth shot in this study just .03% died.

　　"Three shots is the magic number, we think, so far," he says.

　　Underlying¹⁷ conditions put you at higher risk

　　Certain medical conditions also increase the risk of serious illness and death from COVID-19 and that's the reason the FDA decided¹⁸ to authorize¹⁴ the additional boosters starting at age 50.

　　"We know that people in the age range from about 50 to 65 — about a third of them have significant comorbidities," said Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation¹⁹ and Research, at a press conference Tuesday. People with heart disease, lung disease, obesity²⁰ and diabetes²¹ are at higher risk for serious illness and death and people over 50 — particularly people of color — are more likely to have an additional risk factor.

　　"So by choosing age 50 and up, to consider those at high risk or higher risk," Marks said. "We felt like we would capture the population that might most benefit from this fourth dose."

　　When it comes to age, "there's no bright cutoff of risk," agrees Wachter.

　　There are likely incremental²² increases in risk, year after year, as a person ages. A 50-year-old typically has lower risk than a 65-year-old, but health status matters, too.

　　"An unhealthy 55-year-old is probably at the same risk as a healthier 65-year-old," Wachter says.

　　Bottom line, risk goes up with age and underlying conditions, and Wachter says many people over 50 may benefit from another dose.

　　"Anyone who has a serious medical condition, I would certainly suggest thinking about getting a booster," says Dr. Preeti Malani, an infectious disease professor at University of Michigan Health. "For my own family, for my parents and my in-laws, this is something that I will recommend," she says. "Because that extra layer of protection does help ensure that if they get COVID, it's going to be milder."

　　Immunocompromised people may need an extra boost

　　Health officials are particularly concerned about people who are immunocompromised because their immune responses to the vaccine tends to wane⁶ faster and they are at higher risk of getting severely²³ ill or dying from COVID-19.

　　That's why anyone 12 or older with certain immunocompromised conditions can now get an additional shot of the Pfizer-BioNTech COVID-19 vaccine, four months after their last dose. A second booster of the Moderna vaccine can be given to people 18 years of age and older.

　　This includes people who have undergone solid organ transplants, or who are living with conditions that have a similar level of immunocompromise.

　　Timing from last dose or infection is important

　　There is mounting evidence of waning²⁴ vaccine protection against serious illness from COVID-19 in older and immunocompromised people, who are at least four to six months past their first booster.

　　Evidence of waning immunity comes from a recent CDC analysis of COVID-19 emergency room visits and hospitalizations visits during the omicron-predominant period. Two months after a third dose, people were 91% protected against hospitalization. But by four months, that protection dropped down to about 78%.

　　"It means that people who were boosted three, four, five, six months ago probably have limited protection against current infection," Malani says.

　　This means a second booster can help shore up that protection, "but it's not going to be long lasting²⁶." So the timing of the additional shot can be tricky²⁷.

　　Right now the rate of viral infections has come down significantly since the peaks in January, but there are signs that infections are rising in some areas. The even more contagious²⁸ omicron variant²⁹ BA.2 is now the dominant²⁵ variant in the U.S., and hospitalizations are also creeping up in some places.

　　Peter Chin-Hong says some people might want to wait to get a booster until a time when cases start to rise in their community and they need the added protection more urgently.

　　He also notes there may be more effective vaccines on the horizon. As vaccine makers³⁰ test omicron-specific vaccines and continue research on vaccines that could fend³¹ off multiple variants³², it may make more sense for people at lower risk to wait.

　　Still, if you're high-risk, you may not want to wait too long. Polls show many vaccinated³³ people held off on a first booster dose when they became available last year. But waiting until you see another outbreak in your community could be risky³⁴.

　　"It reminds me a little bit of trying to time the stock market. It turns out nobody's actually good at it," Wachter says. If there's another outbreak on the horizon, it's best to maximize your protection in advance of it.

　　There's one more factor to consider when deciding on the timing of a fourth dose: Have you had a recent COVID-19 infection? If you've had three shots and you've had an omicron infection sometime between December and now, "I think it's reasonable to wait." Wachter says. He says a recent infection likely puts a person in a similar immunologic state as a second booster.

　　Rob Stein and Michaeleen Doucleff contributed to this report.

1 timing   

n.时间安排，时间选择

参考例句：

• The timing of the meeting is not convenient.会议的时间安排不合适。
• The timing of our statement is very opportune.我们发表声明选择的时机很恰当。

2 transcript   

n.抄本，誊本，副本，肄业证书

参考例句：

• A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
• They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。

3 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。

4 aged   

adj.年老的，陈年的

参考例句：

• He had put on weight and aged a little.他胖了，也老点了。
• He is aged,but his memory is still good.他已年老，然而记忆力还好。

5 wanes   

v.衰落( wane的第三人称单数 )；（月）亏；变小；变暗淡

参考例句：

• The moon waxes till it becomes full, and then wanes. 月亮渐盈，直到正圆，然后消亏。 来自《现代汉英综合大词典》
• The moon waxes and wanes every month. 月亮每个月都有圆缺。 来自《简明英汉词典》

6 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。

7 lining   

n.衬里，衬料

参考例句：

• The lining of my coat is torn.我的外套衬里破了。
• Moss makes an attractive lining to wire baskets.用苔藓垫在铁丝篮里很漂亮。

8 eligible   

adj.有条件被选中的；(尤指婚姻等)合适(意)的

参考例句：

• He is an eligible young man.他是一个合格的年轻人。
• Helen married an eligible bachelor.海伦嫁给了一个中意的单身汉。

9 Founder   

n.创始者，缔造者

参考例句：

• He was extolled as the founder of their Florentine school.他被称颂为佛罗伦萨画派的鼻祖。
• According to the old tradition,Romulus was the founder of Rome.按照古老的传说，罗穆卢斯是古罗马的建国者。

10 waned   

v.衰落( wane的过去式和过去分词 )；（月）亏；变小；变暗淡

参考例句：

• However,my enthusiasm waned.The time I spent at exercises gradually diminished. 然而，我的热情减退了。我在做操上花的时间逐渐减少了。 来自《用法词典》
• The bicycle craze has waned. 自行车热已冷下去了。 来自《现代汉英综合大词典》

11 considerably   

adv.极大地；相当大地；在很大程度上

参考例句：

• The economic situation has changed considerably.经济形势已发生了相当大的变化。
• The gap has narrowed considerably.分歧大大缩小了。

12 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。

13 authorized   

a.委任的，许可的

参考例句：

• An administrative order is valid if authorized by a statute.如果一个行政命令得到一个法规的认可那么这个命令就是有效的。

14 authorize   

v.授权，委任；批准，认可

参考例句：

• He said that he needed to get his supervisor to authorize my refund.他说必须让主管人员批准我的退款。
• Only the President could authorize the use of the atomic bomb.只有总统才能授权使用原子弹。

15 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。

16 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

17 underlying   

adj.在下面的，含蓄的，潜在的

参考例句：

• The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
• This word has its underlying meaning.这个单词有它潜在的含义。

18 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

19 evaluation   

n.估价，评价；赋值

参考例句：

• I attempted an honest evaluation of my own life.我试图如实地评价我自己的一生。
• The new scheme is still under evaluation.新方案还在评估阶段。

20 obesity   

n.肥胖，肥大

参考例句：

• One effect of overeating may be obesity.吃得过多能导致肥胖。
• Sugar and fat can more easily lead to obesity than some other foods.糖和脂肪比其他食物更容易导致肥胖。

21 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

22 incremental   

adj.增加的

参考例句：

• For logic devices, the incremental current gain is very important. 对于逻辑器件来说，提高电流增益是非常重要的。 来自辞典例句
• By using an incremental approach, the problems involving material or geometric nonlinearity have been solved. 借应用一种增量方法，已经解决了包括材料的或几何的非线性问题。 来自辞典例句

23 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

24 waning   

adj.（月亮）渐亏的，逐渐减弱或变小的n.月亏v.衰落( wane的现在分词 )；（月）亏；变小；变暗淡

参考例句：

• Her enthusiasm for the whole idea was waning rapidly. 她对整个想法的热情迅速冷淡了下来。
• The day is waning and the road is ending. 日暮途穷。 来自《现代汉英综合大词典》

25 dominant   

adj.支配的，统治的；占优势的；显性的；n.主因，要素，主要的人(或物)；显性基因

参考例句：

• The British were formerly dominant in India.英国人从前统治印度。
• She was a dominant figure in the French film industry.她在法国电影界是个举足轻重的人物。

26 lasting   

adj.永久的，永恒的；vbl.持续，维持

参考例句：

• The lasting war debased the value of the dollar.持久的战争使美元贬值。
• We hope for a lasting settlement of all these troubles.我们希望这些纠纷能获得永久的解决。

27 tricky   

adj.狡猾的，奸诈的；(工作等)棘手的，微妙的

参考例句：

• I'm in a rather tricky position.Can you help me out?我的处境很棘手，你能帮我吗？
• He avoided this tricky question and talked in generalities.他回避了这个非常微妙的问题，只做了个笼统的表述。

28 contagious   

adj.传染性的，有感染力的

参考例句：

• It's a highly contagious infection.这种病极易传染。
• He's got a contagious laugh.他的笑富有感染力。

29 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。

30 makers   

n.制造者，制造商（maker的复数形式）

参考例句：

• The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
• The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》

31 fend   

v.照料（自己），（自己）谋生，挡开，避开

参考例句：

• I've had to fend for myself since I was 14.我从十四岁时起就不得不照料自己。
• He raised his arm up to fend branches from his eyes.他举手将树枝从他眼前挡开。

32 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

33 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？

34 risky   

adj.有风险的，冒险的

参考例句：

• It may be risky but we will chance it anyhow.这可能有危险，但我们无论如何要冒一冒险。
• He is well aware how risky this investment is.他心里对这项投资的风险十分清楚。