VOA慢速英语--专家寻找新冠病毒长期症状的病因

American Rachel Van Lear developed signs, also called symptoms, of COVID-19 on March 11, 2020. That same day, medical experts declared the disease a pandemic, meaning the new coronavirus was spreading internationally.

Now, a year later, Van Lear is still waiting for her COVID-19 symptoms to disappear -- and for experts to come up with some answers.

The Texas woman is among tens of thousands of COVID patients known as long-haulers. Long-haulers have symptoms that continue or reappear months after they first became infected with coronavirus.

It is unclear how many people are experiencing the condition and why it is happening. "We're faced with a mystery," said Dr. Francis Collins, chief of the United States National Institutes of Health.

How many people are affected¹, and how long does it last? Is it limited to COVID-19 disease or can other infections lead to the condition? Could some symptoms be unrelated to COVID-19?

The U.S. Congress is providing $1 billion to Collins' agency, the NIH, to seek answers for those questions and more. So, the NIH is designing studies to follow at least 20,000 people who have had COVID-19.

Collins said the agency has never dealt with a long-hauler condition as widespread before. "We don't have time to waste," he said about the research.

There have been an estimated 30 million U.S. cases of COVID-19, and 119 million worldwide. Even a small percentage of patients that develop long-term health issues could become a major problem.

The many reported symptoms of long-haul COVID include extreme tiredness, pain and shortness of breath. Sleeping problems, and difficulty thinking, often called "brain fog," are also common.

And, medical experts have reported organ damage among long-haulers, including lung scarring³ and enlarging of the heart.

Scientists aim to understand whether these symptoms are directly linked to the virus or to some other health issue.

"Is it just a very delayed recovery or is it something even more alarming and something that becomes the new normal?" Collins said.

There are few stories about what might be causing the long-lasting symptoms. One is that the virus remains⁴ in the body at very low levels but still causes organ or tissue damage.

Another possibility is that the virus activates⁵ the body's natural defense⁶ system and somehow prevents that system from returning to normal.

A third idea is that the virus causes small blockages⁷ to form in blood vessels⁸, the tubes through which blood travels.

The 35-year old Van Lear says she was in great health when she got COVID-19. She was a busy mother of three who exercised often.

First came a chest cold, then a rise in body temperature. Testing showed she did not have a flu infection.

Soon after, she developed severe headaches, fatigue⁹ and stomach sickness. Her symptoms were so severe she sought emergency room treatment.

"I was very scared because no one could tell me what was going to happen to me," Van Lear said.

Over the next several months, symptoms would come and go: burning lungs, a very fast heartbeat, shaking hands and hair loss. While most have disappeared, she still sometimes experiences a racing¹⁰ heartbeat.

Van Lear is a member of Survivor¹¹ Corps¹², one of several online support groups formed during the COVID health crisis¹³. The group has thousands of members. Some are taking part in studies to help speed research.

Words in This Story

scar² – v. to make marks on (something) that show damage or wear

alarm – v. to cause (someone) to feel a sense of danger : to worry or frighten (someone)

1 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

2 scar   

n.伤疤，伤痕，创伤

参考例句：

• This scar is from the bite of a dog.这是狗咬后留下的伤疤。
• The tragedy left a scar on her mind.这个悲剧给她造成精神上的创伤。

3 scarring   

[医] 瘢痕形成；伤疤

参考例句：

• Cystic acne usually results in deep pitting or scarring of the skin. 囊肿型痤疮往往导致皮肤凹陷或留下疤痕。
• The cut on his leg is scarring well. 他大腿上的伤口结疤情形良好。

4 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

5 activates   

使活动，起动，触发( activate的第三人称单数 )

参考例句：

• Activates the window and displays it in its current size and position. 激活窗口，保持当前的大小及位置不变。
• Pulling out the alarm switch activates alarm and pushing it deactivates it. 闹钟的开和关是通过拔出和按入闹铃开关实现的。

6 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。

7 blockages   

n.堵塞物( blockage的名词复数 )；堵塞，阻塞

参考例句：

• The storms could increase the risks posed by river blockages. 暴风雨会增加因河道堵塞所造成的危险。 来自互联网
• An angiogram shows the location and severity of blockages in blood vessels. 冠状动脉造影能够显示血管内的阻塞位置以及阻塞的严重程度。 来自互联网

8 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

9 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。

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 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。

12 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。

13 crisis   

n.危机，危急关头，决定性时刻，关键阶段

参考例句：

• He had proved that he could be relied on in a crisis.他已表明，在紧要关头他是可以信赖的。
• The topic today centers about the crisis in the Middle East.今天课题的中心是中东危机。