Researchers Explore Causes of Long COVID
2023-01-17
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1A British historian, an Italian archaeologist and an American teacher all have something in common.
2The three women are credited with describing and naming the condition known as long COVID in early 2020.
3Almost three years into the pandemic, scientists are still trying to figure out why some people get long COVID and why a small percentage - including the three women - have lasting symptoms.
4Rachel Pope, the historian, is from the British city of Liverpool.
5She posted on Twitter about her symptoms in late March 2020, after a coronavirus infection.
6A few months later, in Italy, Elisa Perego tweeted about her sickness also and used the term "long COVID" in the post.
7And, that same year, Amy Watson of Portland, Oregon, founded a Facebook support group for people, like her, who were suffering from long COVID.
8She identified them as "long haulers," a term used in the trucking industry.
9The name stuck.
10Millions of people worldwide report having long COVID.
11The symptoms include lung damage, difficulty thinking and remembering, extreme tiredness, and other problems.
12Evidence suggests most people get better within a year.
13But recent data show that long COVID has played a part in more than 3,500 U.S. deaths.
14Many studies suggest that women are more likely than men to develop long COVID.
15There could be biological reasons.
16Women's immune systems generally have stronger reactions to viruses, bacteria, and other germs, said Sabra Klein, an immune system expert at Johns Hopkins University.
17Women are also much more likely than men to have autoimmune diseases, where the body mistakenly attacks its own healthy tissue.
18Some scientists believe long COVID can result from an autoimmune response caused by the virus.
19Women's bodies are also more likely to have more fat tissue.
20New research suggests the coronavirus may hide in fat after infection.
21Scientists also are studying whether women's changing hormone levels may increase the risks.
22Yet there are other possible issues at work.
23Women are more likely than men to seek health care, Klein said.
24She added that often women are more sensitive to changes in their bodies.
25"I don't think we should ignore that," she said, adding that biology and behavior are probably both at play.
26Several studies suggest the Epstein-Barr virus could play a part in some cases of long COVID.
27Epstein-Barr is a very common virus.
28It has infected an estimated 90 percent of the U.S. population.
29The virus' effects can differ greatly among those infected.
30Some patients might develop the disease mononucleosis, for example.
31Others, however, may not be sickened at all by an Epstein-Barr infection.
32Inflammation caused by coronavirus infection can activate or reactivate some viruses in the body, said Dr. Timothy Henrich.
33He is an expert with the University of California, San Francisco.
34Henrich is among researchers who have found immune markers pointing to Epstein-Barr reactivation in the blood of long COVID patients.
35Not all long COVID patients have these markers.
36But it's possible that Epstein-Barr is causing symptoms in those who do, although scientists say more study is needed.
37Obesity is a risk factor for severe COVID-19 infections and scientists are trying to understand why.
38Stanford University researchers are among those who have found evidence that the coronavirus can infect fat cells.
39In a recent study, they found the virus and signs of inflammation in fat tissue taken from people who had died from COVID-19.
40Lab tests showed that the virus can reproduce in fat tissue.
41That raises the possibility that fat tissue could serve as a storage area, possibly fueling long COVID.
42Dr. Lawrence Purpura is an infectious disease expert at Columbia University in New York.
43He said about patients with long COVID, "The majority of patients will eventually recover...It's important for people to know that."
44Still, the women who helped the world recognize the condition of long COVID remain concerned about recovery.
45Perego developed heart, lung and other problems and remains seriously sick.
46The 44-year-old says she knows that scientists have learned a lot in a short time.
47But, "there is a gap," she said, between long COVID research and medical care.
48Watson, who is 59, says she has "never had any kind of recovery."
49She experiences severe headaches, digestive trouble and nerve and foot problems. Recently she developed anemia.
50She wishes the medical community had a more organized process for treating long COVID.
51Doctors say not knowing the underlying cause or causes makes that difficult.
52"I just want my life back," Watson said, "and it's not looking like that's all that possible."
53I'm Ashley Thompson. And I'm John Russell.
1A British historian, an Italian archaeologist and an American teacher all have something in common. 2The three women are credited with describing and naming the condition known as long COVID in early 2020. 3Almost three years into the pandemic, scientists are still trying to figure out why some people get long COVID and why a small percentage - including the three women - have lasting symptoms. 4Background 5Rachel Pope, the historian, is from the British city of Liverpool. She posted on Twitter about her symptoms in late March 2020, after a coronavirus infection. A few months later, in Italy, Elisa Perego tweeted about her sickness also and used the term "long COVID" in the post. And, that same year, Amy Watson of Portland, Oregon, founded a Facebook support group for people, like her, who were suffering from long COVID. She identified them as "long haulers," a term used in the trucking industry. The name stuck. 6Millions of people worldwide report having long COVID. The symptoms include lung damage, difficulty thinking and remembering, extreme tiredness, and other problems. Evidence suggests most people get better within a year. But recent data show that long COVID has played a part in more than 3,500 U.S. deaths. 7Women more likely to suffer from long COVID 8Many studies suggest that women are more likely than men to develop long COVID. 9There could be biological reasons. 10Women's immune systems generally have stronger reactions to viruses, bacteria, and other germs, said Sabra Klein, an immune system expert at Johns Hopkins University. 11Women are also much more likely than men to have autoimmune diseases, where the body mistakenly attacks its own healthy tissue. Some scientists believe long COVID can result from an autoimmune response caused by the virus. 12Women's bodies are also more likely to have more fat tissue. New research suggests the coronavirus may hide in fat after infection. Scientists also are studying whether women's changing hormone levels may increase the risks. 13Yet there are other possible issues at work. Women are more likely than men to seek health care, Klein said. She added that often women are more sensitive to changes in their bodies. 14"I don't think we should ignore that," she said, adding that biology and behavior are probably both at play. 15Other viruses 16Several studies suggest the Epstein-Barr virus could play a part in some cases of long COVID. 17Epstein-Barr is a very common virus. It has infected an estimated 90 percent of the U.S. population. The virus' effects can differ greatly among those infected. Some patients might develop the disease mononucleosis, for example. Others, however, may not be sickened at all by an Epstein-Barr infection. 18Inflammation caused by coronavirus infection can activate or reactivate some viruses in the body, said Dr. Timothy Henrich. He is an expert with the University of California, San Francisco. 19Henrich is among researchers who have found immune markers pointing to Epstein-Barr reactivation in the blood of long COVID patients. 20Not all long COVID patients have these markers. But it's possible that Epstein-Barr is causing symptoms in those who do, although scientists say more study is needed. 21Obesity 22Obesity is a risk factor for severe COVID-19 infections and scientists are trying to understand why. 23Stanford University researchers are among those who have found evidence that the coronavirus can infect fat cells. In a recent study, they found the virus and signs of inflammation in fat tissue taken from people who had died from COVID-19. 24Lab tests showed that the virus can reproduce in fat tissue. That raises the possibility that fat tissue could serve as a storage area, possibly fueling long COVID. 25Hope and concerns 26Dr. Lawrence Purpura is an infectious disease expert at Columbia University in New York. He said about patients with long COVID, "The majority of patients will eventually recover...It's important for people to know that." 27Still, the women who helped the world recognize the condition of long COVID remain concerned about recovery. 28Perego developed heart, lung and other problems and remains seriously sick. 29The 44-year-old says she knows that scientists have learned a lot in a short time. But, "there is a gap," she said, between long COVID research and medical care. 30Watson, who is 59, says she has "never had any kind of recovery." She experiences severe headaches, digestive trouble and nerve and foot problems. Recently she developed anemia. 31She wishes the medical community had a more organized process for treating long COVID. Doctors say not knowing the underlying cause or causes makes that difficult. 32"I just want my life back," Watson said, "and it's not looking like that's all that possible." 33I'm Ashley Thompson. And I'm John Russell. 34Lindsey Tanner reported on this study for the Associated Press. John Russell adapted it for VOA Learning English. 35___________________________________________________________________ 36Words in This Story 37symptom -- n. a change in the body or mind which indicates that a disease is present 38immune -- adj. of or relating to the body's immune system 39autoimmune - adj. of, relating to antibodies or T cells that attack molecules, cells, or tissues of the organism producing them 40hormone - n. a natural substance that is produced in the body and that influences the way the body grows or develops 41anemia - n. medical: a condition in which a person has fewer red blood cells than normal and feels very weak and tired