美国国家公共电台 NPR--A new dominant omicron strain in the U.S. is driving up cases — and reinfections

A new dominant¹ omicron strain in the U.S. is driving up cases — and reinfections

Transcript²

For much of the pandemic, the only silver lining³ to coming down with a case of COVID-19 was that you likely wouldn't catch it again for a while (though there isn't exactly a definitive⁴ answer on how long that period of immunity⁵ typically lasts).

Increasingly, however, more people appear to be contracting the virus multiple times in relatively⁶ quick succession, as another omicron subvariant sweeps through the U.S.

The BA.5 variant⁷ is now the most dominant strain of COVID-19 in the country, according to the Centers for Disease Control and Prevention. And while it's hard to get an exact count — given how many people are taking rapid tests at home — there are indications that both reinfections and hospitalizations are increasing.

For example: Some 31,000 people across the U.S. are currently hospitalized with the virus, with admissions up 4.5% compared to a week ago. And data from New York state shows that reinfections started trending upwards⁸ again in late June.

Dr. Bob Wachter, the chair of the Department of Medicine at the University of California, San Francisco, says BA.5 is highly transmissible and manages to at least partially⁹ sidestep some of the immunity people may have from prior infections and vaccinations¹⁰.

"Not only is it more infectious, but your prior immunity doesn't count for as much as it used to," he explains. "And that means that the old saw that, 'I just had COVID a month ago, and so I have COVID immunity superpowers, I'm not going to get it again' — that no longer holds."

So just how worried should you be, especially if you're vaccinated¹¹ and taking precautions like wearing masks in crowds? Here's what some public health experts make of the latest surge.

Is BA.5 more dangerous?

So far there is no evidence that this variant causes more serious illness. And infectious disease experts say that even though new infections are on the rise, the impact of BA.5 is unlikely to be on the scale of the surge we saw last winter — in part because the country is better equipped to manage it.

The U.S. is averaging about 300 deaths a day, compared to 3,000 last winter. Dr. Anna Durbin, a professor at the Johns Hopkins University School of Medicine, says the combination of prior infections and vaccinations is still protective, and COVID-19 treatments are better.

"Most people have some underlying¹² immunity that is helpful in fighting the virus," she explains. "We have antivirals ... And I think that because of that ... we're not seeing a rise in deaths. And that's very reassuring¹³. It tells me that even this virus, even BA.5, is not so divergent that it is escaping all arms of the immune system."

She adds that new booster shots specifically targeting omicron — which could roll out as soon as this fall — should also be helpful in preventing serious illness and deaths.

Are there long-term consequences for people who get COVID-19 multiple times?

Findings of a pre-print study published in June suggest that people who get sick multiple times may have a higher risk of long-COVID symptoms.

Dr. Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis, looked at thousands of cases of reinfection and saw a wide range of problems in the months that followed: certain respiratory conditions, cough, shortness of breath, fatigue¹⁴, brain fog and other conditions including metabolic¹⁵ disease, cardiac disease, kidney disease and diabetes¹⁶.

"Altogether, we concluded that reinfection contributes to additional risk," Al-Aly says. "So even if you're vaccinated ... it's absolutely best to avoid reinfection."

And a study published last week in the journal Cell concludes that repeat infections are likely.

Researchers studied blood samples from people who had been vaccinated and boosted, and they found they had a reduced ability to neutralize¹⁷ the BA.5 virus, compared to prior sub-variants, BA.1 and BA.2.

In addition, blood from people who had breakthrough infections from BA.1 also showed reduced neutralization¹⁸, "suggesting that repeat Omicron infections are likely in the population," the authors conclude.

What can people do to protect themselves?

There are steps you can take to reduce your exposure to the virus, like masking up in crowded indoor spaces. Here's how to step up your mask game.

Plus, children under the age of 5 are finally eligible¹⁹ to get vaccinated (and while many parents are hesitant, public health experts are encouraging them not to wait any longer). And adults ages 50 and older, as well as those over 12 with certain underlying conditions, can get a second booster shot.

And, if you already have plans to travel or attend gatherings²⁰ this summer, check out these tips for protecting yourself outdoors, improving indoor airflow and what to do if you get sick while on vacation.

1 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。

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 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。

4 definitive   

adj.确切的，权威性的；最后的，决定性的

参考例句：

• This book is the definitive guide to world cuisine.这本书是世界美食的权威指南。
• No one has come up with a definitive answer as to why this should be so.至于为什么该这样，还没有人给出明确的答复。

5 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。

6 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

7 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。

8 upwards   

adv.向上，在更高处...以上

参考例句：

• The trend of prices is still upwards.物价的趋向是仍在上涨。
• The smoke rose straight upwards.烟一直向上升。

9 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。

10 vaccinations   

n.种痘，接种( vaccination的名词复数 )；牛痘疤

参考例句：

• Vaccinations ensure one against diseases. 接种疫苗可以预防疾病。 来自《简明英汉词典》
• I read some publicity about vaccinations while waiting my turn at the doctor's. 在医生那儿候诊时，我读了一些关于接种疫苗的宣传。 来自《简明英汉词典》

11 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？

12 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。

13 reassuring   

a.使人消除恐惧和疑虑的，使人放心的

参考例句：

• He gave her a reassuring pat on the shoulder. 他轻拍了一下她的肩膀让她放心。
• With a reassuring pat on her arm, he left. 他鼓励地拍了拍她的手臂就离开了。

14 fatigue   

n.疲劳，劳累

参考例句：

• The old lady can't bear the fatigue of a long journey.这位老妇人不能忍受长途旅行的疲劳。
• I have got over my weakness and fatigue.我已从虚弱和疲劳中恢复过来了。

15 metabolic   

adj.新陈代谢的

参考例句：

• Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。
• A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。

16 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。

17 neutralize   

v.使失效、抵消，使中和

参考例句：

• Nothing could neutralize its good effects.没有什么能抵消它所产生的好影响。
• Acids neutralize alkalis and vice versa.酸能使碱中和碱，亦能使酸中和。

18 neutralization   

n.中立化，中立状态，中和

参考例句：

• Neutralization is the interaction of a base and an acid. 中和作用是碱和酸的相互作用。 来自辞典例句
• The neutralization equivalent of the polymer is 750(theoretical-681). 聚和物的中和当量为750（理论上为681）。 来自辞典例句

19 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。

20 gatherings   

聚集( gathering的名词复数 )； 收集； 采集； 搜集

参考例句：

• His conduct at social gatherings created a lot of comment. 他在社交聚会上的表现引起许多闲话。
• During one of these gatherings a pupil caught stealing. 有一次，其中一名弟子偷窃被抓住。