The number of severe Covid-19 courses in Germany is falling. But doctors warn that long-term damage can also be expected in those who have recovered. Studies on a close relative of Sars-CoV-2 provide information about possible long-term effects.
Of course, nobody knows what long-term consequences Covid-19 will have. Because the pathogen Sars-CoV-2 and the disease it causes has only been known for nine months. However, the Jena doctor Andreas Stallmach estimates that more than half of those who had to be treated in a clinic for Covid-19 have consequential damage. But there are also people with only mild disease who suffer from long-term effects, according to Stallmach.
But what possible long-term consequences could Covid-19 cause? One thing is clear: the pathogen attacks first and foremost the lungs, which is why it leaves traces in this organ even after recovery. One published in August study had examined Covid-19 genesis, which had to be treated in hospital. Of these, 70 percent still had shortness of breath a month after they were discharged, and 13.5 percent still used oxygen at home.
How long these symptoms will last is unclear. However, there could be indications from experience with the closely related Sars virus, which moved across the earth in a small pandemic from 2002 to 2003. As part of a study between 2003 and 2018, researchers followed the health development of 71 people who were infected with Sars. The result: of these, almost five percent still had visible lung damage after 15 years. In even more than a third the ability of the lungs to absorb oxygen was restricted.
“Almost all organs are affected”
But not only the lungs are likely to show symptoms in the long term. Because it is now clear that Covid-19 is not a pure respiratory disease. “The viruses can infect almost all organs and consequential damage can occur in almost all organs,” says Stallmach. In addition to shortness of breath, this could also include difficulty concentrating and depression, including stomach and intestinal complaints. A new study shows for the first time that the virus affects some people penetrates the brain cells.
The heart is also a weak point. Even during the acute illness, about a third of the patients show symptoms that are related to the cardiovascular system, said the Chinese cardiologist Mao Chen to the specialist magazine “Nature”. According to this, the heart is particularly sensitive to overreactions of the immune system, as has been observed especially in adult Covid 19 patients with severe courses – the so-called cytokine storms.
Possible consequences for the heart and circulation: For example, a deformation or hardening of the heart muscle, which affects the pumping process. According to Chen, other patients had pulmonary embolism, in which blood vessels in the lungs are usually blocked by blood clots. However, the pathogen can also infect the cells in the inner layer of blood vessels and thereby damage them, throughout the body.
However, Covid-19 not only leads to a dangerous overreaction of the immune system, but in some cases also weakens it. In the long term, this could mean that patients may be more susceptible to infections from other pathogens even after they have recovered. Experience with the Sars virus from 2002 to 2003 also gives an indication of this. The predecessor of Sars-CoV-2 is known to dampen the immune system by inhibiting the production of interferons – these are antiviral messenger substances that Usually putting the body’s defenses into an alarm state.
Mysterious symptom of exhaustion
Another long-term consequence of Covid-19 that is still little understood is severe exhaustion. In the past few months there have been increasing reports of people suffering from paralyzing fatigue and malaise after falling ill with Covid-19, according to the “Nature” report. You have difficulty getting up in the morning and can only work for a few minutes or hours at a time. According to study from Italy on 143 Covid 19 patients who had left the hospital, a little more than half complained two months later of exhaustion and around 40 percent of shortness of breath.
However, experts are currently struggling to link Covid-19 to exhaustion. But even with this symptom there are similarities to the older Sars virus: One study from 2011 described 22 former Sars patients who were unable to work 13 to 36 months after infection. Another study from 2009 found 40 percent of Sars convalescents to be chronically exhausted.
According to another study, Covid-19 can apparently also have psychological consequences such as trauma, anxiety and sleep disorders, and depression. One month after their discharge from the hospital, more than half of the 402 patients observed showed at least one of these clinical pictures, according to a study by the San Raffaele Hospital in Milan. The severity of the disorders corresponded to the severity of the disease.