VOA健康报道--奥密克戎加剧了人们对长期新冠病毒及其原因的担忧

Omicron Increases Worries about ‘Long COVID’

It has been more than one year since Rebekah Hogan got COVID-19. She still suffers from pain and tiredness. She struggles with thinking and remembering. Her condition makes her unable to do her nursing job or do normal household activities.

Hogan's husband and three children also have signs of the condition. The family lives in Latham, New York.

Her experience with COVID-19 has her questioning her worth as a wife and mother.

"Is this permanent? Is this the new norm?" said the 41-year-old Hogan. "I want my life back."

There are estimates that more than one-third of people infected with COVID-19 will develop long-lasting problems. Scientists are trying to understand the cause of so-called "long COVID" and find treatments for it.

It is too soon to know whether people infected with the fast-spreading Omicron variant¹ will develop mysterious symptoms. Signs of long COVID usually appear weeks after first getting sick. But some experts think a wave of long COVID is likely. And they say doctors need to be prepared for it.

The U.S. National Institutes of Health is carrying out research on the condition, with the help of the $1 billion it received from Congress. Medical centers for studying long COVID are appearing around the world. Such centers have connections with places like Stanford University in California and University College London.

Why does it happen?

Scientists have different theories for why long COVID happens. Support is building around a few of the major theories.

One theory is that a small amount of the virus stays in the body long past the illness. This causes inflammation that leads to long COVID.

Another theory says that inactive viruses in the body are reactivated. A recent study that appeared in the publication Cell pointed³ to Epstein-Barr in the blood as one of four possible risk factors. Epstein-Barr is a virus that causes mononucleosis – a disease that makes people very tired and weak for a long time.

The study's findings must be confirmed by more research.

A third theory is that autoimmune reactions develop after severe COVID-19. In a normal immune reaction, viral infections activate² antibodies that fight virus proteins. But sometimes, antibodies mistakenly attack normal cells. This action is thought to play a part in autoimmune diseases such as lupus and multiple sclerosis.

Another possibility is that very small blood clots⁵ in the blood play a part in long COVID. Many COVID-19 patients develop high levels of inflammatory molecules⁶ that can lead to abnormal clotting⁷.

In her laboratory at Stellenbosch University in South Africa, scientist Resia Pretorius has found small clots in blood samples from patients with COVID-19 and in those who later developed long COVID. She also found high levels of protein in blood plasma⁸ that prevented the normal breakdown⁹ of these clots.

Pretorius believes that these clotting abnormalities continue in many patients after a coronavirus infection. She also believes they reduce oxygen going to cells and tissue throughout the body. This lack of oxygen can cause many of the symptoms linked to long COVID.

It can affect nearly anyone

A full list of symptoms that make up long COVID does not exist. The most common ones are tiredness, problems with memory and thinking, loss of taste and smell. Also included are shortness of breath, sleep problems and mental health issues.

Long COVID affects adults of all ages as well as children. Research shows it is more common among those who were hospitalized, but it also affects those who were not. It is more common among women.

Jacki Graham's experience with COVID-19 at the beginning of the pandemic was not bad enough to put her in the hospital. But months later, the 64-year-old experienced breathlessness and a racing¹⁰ heart. She could not taste or smell. Her blood pressure increased.

In the fall of 2020, she started becoming so tired that her morning exercise would send her back to bed.

"Six months ago, I would have told you COVID has ruined my life," Graham said.

Hogan, the New York nurse, also did not go to the hospital with COVID-19. But she has struggled since the infection.

Hogan's doctors think autoimmune problems and a pre-existing connective tissue disorder¹¹ may have made her likely to develop the condition.

Possible answers

There are no treatments approved for long COVID. Some patients, however, see improvements from painkillers¹², drugs used for other conditions, and physical therapy. But more help may come soon.

Immunobiologist Akiko Iwasaki is studying the possibility that COVID-19 vaccination¹³ might reduce long COVID symptoms. Her team at Yale University in Connecticut is working with a patient group called Survivor¹⁴ Corps¹⁵. Their research involves vaccinating¹⁶ unvaccinated long COVID patients as a possible treatment.

Two recently released studies offer early evidence that being vaccinated¹⁷ before getting COVID-19 could help prevent long COVID, or at least reduce its severity. Both studies were done before the Omicron version of the new coronavirus appeared.

I'm Ashley Thompson.

Words in This Story

symptoms –n. (pl.) changes in the body or mind that shows that a disease is present

inflammation –n. a condition in which a part of your body becomes red, bigger than normal and painful

risk factor –n. something that increases risk; a condition that makes it more likely that a person might get a disease

autoimmune –adj. relating to antibodies or cells that attack molecules, cells or tissue that is healthy

blood clot⁴ –n. a mass of dried blood that stops the flow of blood in the body and that can cause serious health problems

plasma –n. the part of blood that is a clear fluid which holds red blood cells and other parts found in the blood

immunobiologist –n. a biologist who studies how living things fight infection

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 activate   

vt.使活动起来，使开始起作用

参考例句：

• We must activate the youth to study.我们要激励青年去学习。
• These push buttons can activate the elevator.这些按钮能启动电梯。

3 pointed   

adj.尖的，直截了当的

参考例句：

• He gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
• She wished to show Mrs.John Dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。

4 clot   

n.凝块；v.使凝成块

参考例句：

• Platelets are one of the components required to make blood clot.血小板是血液凝固的必须成分之一。
• The patient's blood refused to clot.病人的血液无法凝结。

5 clots   

n.凝块( clot的名词复数 )；血块；蠢人；傻瓜v.凝固( clot的第三人称单数 )

参考例句：

• When you cut yourself, blood clots and forms a scab. 你割破了，血会凝固、结痂。 来自《简明英汉词典》
• Milk clots when it turns sour. 奶变酸就凝块。 来自《现代英汉综合大词典》

6 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

7 clotting   

v.凝固( clot的现在分词 )；烧结

参考例句：

• The study was also based only on the one anti-clotting drug. 所用抗血栓药物也仅限于一种。 来自互联网
• A plasma protein that is converted into thrombin during blood clotting. 凝血原酶一种血浆蛋白质，在血液凝聚时转化成凝血''。'酵'。''''。'素'。''。 来自互联网

8 plasma   

n.血浆，细胞质，乳清

参考例句：

• Keep some blood plasma back for the serious cases.留一些血浆给重病号。
• The plasma is the liquid portion of blood that is free of cells .血浆是血液的液体部分，不包含各种细胞。

9 breakdown   

n.垮，衰竭；损坏，故障，倒塌

参考例句：

• She suffered a nervous breakdown.她患神经衰弱。
• The plane had a breakdown in the air,but it was fortunately removed by the ace pilot.飞机在空中发生了故障，但幸运的是被王牌驾驶员排除了。

10 racing   

n.竞赛，赛马；adj.竞赛用的，赛马用的

参考例句：

• I was watching the racing on television last night.昨晚我在电视上看赛马。
• The two racing drivers fenced for a chance to gain the lead.两个赛车手伺机竞相领先。

11 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

12 painkillers   

n.止痛药( painkiller的名词复数 )

参考例句：

• The doctor gave him some painkillers to ease the pain. 医生给了他一些止疼片以减缓疼痛。 来自辞典例句
• The primary painkillers - opiates, like OxyContin - are widely feared, misunderstood and underused. 人们对主要的镇痛药——如鸦片剂奥施康定——存在广泛的恐惧、误解，因此没有充分利用。 来自时文部分

13 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。

14 survivor   

n.生存者，残存者，幸存者

参考例句：

• The sole survivor of the crash was an infant.这次撞车的惟一幸存者是一个婴儿。
• There was only one survivor of the plane crash.这次飞机失事中只有一名幸存者。

15 corps   

n.(通信等兵种的)部队；(同类作的)一组

参考例句：

• The medical corps were cited for bravery in combat.医疗队由于在战场上的英勇表现而受嘉奖。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

16 vaccinating   

给…接种疫苗( vaccinate的现在分词 )； 注射疫苗，接种疫苗

参考例句：

• At first blush, vaccinating the wolves against rabies seems a simple solution. 乍一看来，为狼群注射防狂犬病疫苗是一种简单的办法。
• Also vaccinating children against misers (measles) has saved many lives. 还有，给儿童进行疫苗接种防止麻疹也挽救了许多生命。

17 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？