Long-term fatigue after Yang Kang, beware of "catching COVID-19"!

More and more people say that they experience symptoms such as fatigue, exhaustion, and light-footed walking after undergoing "Yang Kang".

This can be simply understood as "post-COVID sequelae". The World Health Organization calls it "post-COVID symptoms" and is now more commonly referred to as "long COVID", which refers to a series of long-term symptoms experienced by some people after being infected with the new coronavirus.

In fact, it is still difficult to determine the specific sequelae of the new crown. Since the base of new crown patients in Europe and the United States is too large, a large number of people are troubled by "new crown". We can understand it based on their research data.

1. Common symptoms

The WHO pointed out that common symptoms of "long COVID" include fatigue, shortness of breath and cognitive dysfunction . These symptoms may appear after the initial recovery from an acute COVID attack or persist after the initial COVID infection.

The CDC said that people with "long COVID" may experience a variety of symptoms, including fatigue or weakness that affects daily life, worsening symptoms after physical or mental work, respiratory and cardiac symptoms, neurological symptoms, digestive system symptoms, etc. These symptoms may last for weeks or months, and sometimes symptoms may even disappear and reappear.

The common symptoms of "long COVID" listed by the UK National Health System include extreme tiredness, shortness of breath, loss of smell, muscle pain, and other possible symptoms include memory and concentration problems ("brain fog"), chest pain or chest tightness, difficulty sleeping (insomnia), palpitations, dizziness, joint pain, depression and anxiety, tinnitus or ear pain, nausea, diarrhea, rash, etc.

Emma Raz, a health expert at the University of Oxford in the UK, believes that among the many possible symptoms of "long-term COVID-19", "brain fog" may be "one of the most disabling and destructive symptoms to date."

2. Susceptible population

The WHO says anyone infected with the coronavirus is likely to experience "post-COVID symptoms," regardless of gender, age or the severity of the initial COVID infection . About 10% to 20% of COVID patients experience persistent symptoms after an acute COVID infection.

According to the US Centers for Disease Control and Prevention, studies have shown that some groups of people may be more susceptible to "long COVID", such as people with underlying health problems before being infected with COVID, people who have not been vaccinated against COVID, and people who develop multisystem inflammatory syndrome during or after being infected with COVID.

Survey data released by the UK National Statistics Office showed that as of early November, more than 2 million people in the UK reported suffering from "long COVID" symptoms. The UK Department of Health and Social Care said that "long COVID" can affect anyone, not just those who are seriously unwell or hospitalized when they are infected with COVID. The UK National Health System pointed out that the chance of long-term symptoms does not seem to be related to the condition when the COVID was first infected, and people with mild symptoms may also have long-term problems.

Researchers at the University of Glasgow in the UK published a paper in the British journal Nature Communications in October, saying that they conducted a long-term survey on "long COVID" among people in Scotland. A total of 33,281 participants were confirmed to be infected with COVID. In a follow-up survey of participants six months, one year, and one and a half years later, the researchers found that among the 31,486 symptomatic infected people, 6% said they had never recovered, and 42% said their bodies had only partially recovered. The study also found that COVID vaccination was associated with a reduced risk of severe symptoms after infection.

3. Duration

The World Health Organization defines post-COVID-19 sequelae as new symptoms that still exist or gradually develop three months after COVID-19 infection, last for more than two months and cannot be explained by other reasons.

The UK National Health System pointed out that long-term symptoms caused by the new coronavirus may last for weeks or months after the infection disappears, and the time needed to recover from them varies from person to person. Recovery from "long COVID" varies, some symptoms can improve quickly, while others last longer.

A research report recently published in the Journal of the American Medical Association Network Open on the 15th of this month said that two years after acute infection with the new coronavirus, more than half of the patients still experienced at least one "long-term new coronavirus" symptom. The study investigated people around 60 years old who were infected with the new coronavirus during the first wave of the epidemic. The results showed that about 60% of the infected people who were hospitalized and about 68% of the infected people who were not hospitalized still had "long-term new coronavirus" symptoms two years later.

Daniel Altman, professor of immunology at Imperial College London, told reporters that research shows that the incidence of long COVID-19 may be underestimated. He said that if the probability of long COVID-19 among all COVID-19 infected people is extrapolated, the number will be huge, far worse than we have expected so far [1].

In short, the symptoms and duration of long COVID vary among different populations, but we can be sure that there are indeed a series of follow-up effects after being infected with COVID. The effects of long COVID may last for weeks, months or even longer, and everyone infected with COVID may be infected.

Metz Medicine points out that the cough, fatigue, shortness of breath, etc. experienced by most "Yangkang" patients cannot be called COVID-19, but are just a normal recovery period (even in the acute stage after infection). So don't be too eager to draw conclusions.

There is no specific medicine for the new coronavirus now, so one can imagine the sequelae of the coronavirus, and further research is still needed.

Recently, a research team from the University of Vienna discovered the pathological mechanism of COVID-19 fatigue syndrome triggered by infection with the new coronavirus - an excessive anti-inflammatory response [2].

Simply put, what patients with COVID-19 experience is not a classic inflammatory response. The long-term fatigue caused by the new coronavirus is not due to inflammation, but rather a "changed" anti-inflammatory process.

In patients with COVID-19, alternating polarized macrophages are formed (Note: Macrophages in the human body are divided into two categories, classically activated M1 macrophages and selectively activated M2 macrophages. Under the attack of the new coronavirus, the common classical pro-inflammatory M1 cells are transformed into tolerant M2 cells, resulting in a change in the anti-inflammatory mode.)

This alteration leads to increased levels of the anti-inflammatory osmolyte taurine and erythrine, a compound that can spontaneously induce sleep, thus causing the fatigue syndrome.

Some people must be asking, how to treat COVID-19? Can it be cured?

Medical research needs to be carried out step by step. The current research on the pathological mechanism of COVID-19 is only the first step. The development of targeted special medicines will definitely take time. So now if the symptoms of COVID-19 affect your work and life, you need symptomatic treatment according to the severity of the symptoms. If the symptoms are mild, you don’t have to worry too much. It is recommended to get vaccinated to prevent it and try to avoid "secondary infection."

References

[1] Xinhuanet, Popular Science: How Much Do You Know About COVID-19?

http://www.news.cn/science/2022-11/25/c_1129160105.htm

[2]KovarikJJ, Bileck A, Hagn G, et al. A multiomics based antiinflammatory immune signature characterizes long COVID-19 syndrome. iScience. 2023 Jan 20;26(1):105717.