Corona helper: no symptoms or severe course?
Researchers give 5 possible reasons
Created: 01/11/2022, 02:51 PM
From: Bedrettin Bölükbasi
When does a serious corona disease occur?
Researchers explain possible factors that determine the course.
© imago images / Ralph Lueger
A corona infection can have a severe course for some, but a mild or even symptom-free course for others.
Researchers explain what this may depend on.
Munich - A corona infection does not always turn out the same.
While some feel all the effects with full severity, end up in the intensive care unit and float or die in mortal danger, others feel only a few of the symptoms or even none at all and are fit again in a short time.
The world has been fighting the pandemic for two years now, but it is still not possible to say in general and with certainty for whom an infection is dangerous and for whom it is less dangerous.
However, researchers believe there are five main factors that can lead to a severe course.
Corona infection: six gene variants possible reason for severe course - researcher calls for vaccination
According to the research, one possible reason is the genetic makeup of the person concerned. As early as the end of 2020, five gene variants were found that can lead to a severe course. For the study, the DNA data of 2,700 corona patients in 208 intensive care units were evaluated, as the
Reuters
news agency reported at the time. The result showed that these gene variants, which are part of the processes leading to antiviral immunity and pneumonia, are a central factor in many severe cases, because they may have an inflammatory effect.
In addition to the five gene variants - IFNAR2, TYK2, OAS1, DPP9 and CCR2 - another variant was recently discovered that favors a severe course. In a report, researchers at Oxford University stated that the LZTFL1 gene variant interfered with the defense reaction of mucosal cells in the lungs and airways. The result: the susceptibility to corona increases. Since this gene variant does not affect the immune defense, but the lungs, a researcher, James Davies, called for vaccination: "People with this risk gene can probably benefit in particular from a vaccination." This can compensate for the increased risk. In Europe, 15 percent of the population apparently carry this gene variant, although this value is significantly higher in South Asia at 60 percent.
Corona infection: the risk of death is higher in men than in women - female hormones support the immune system
In fact, gender can also be the deciding factor for a severe course of the disease after a corona infection.
Although men and women contract the deadly virus with a similar frequency, the death rate in men is significantly higher.
The reason: the different immune reactions to the virus.
In a study at the end of 2020, British researchers found that men after being infected with corona are more likely to resort to the innate immune system, which is weaker than the acquired immune system when it comes to dealing with the virus.
The women resort to the latter.
As a result, the chance of survival in men is significantly lower.
In addition, the blood of men has a higher concentration of ACE-2 receptors on cells to which the Covid-19 docks.
When it comes to hormones, too, men are again losing out to women.
The estrogen stimulates the immune defense, while the male testosterone inhibits the body's own defenses.
Corona infection: age and previous illness are important factors - older people with previous illnesses are severely affected
Age also plays a role.
Older people have a significantly higher risk of death than younger patients under 65, as a study by the American Stanford University has shown.
Even if you are under 65 years of age, the risk is twice as high in patients with previous illnesses.
After all, according to researchers, pre-existing conditions such as high blood pressure, cardiovascular diseases, asthma, diabetes, lung diseases or obesity are another factor that can lead to a serious course of the disease.
Cancer treatment with the drug rituximab also means an increased risk, because the use of rituximab affects the B cells of the immune system, which are necessary for the production of antibodies against viruses.
Corona infection: immune type also decisive in severe disease - inflammation in the body
The severity of a corona infection can also depend on the patient's immune type.
Differences in immune cells and above all the excessive release of inflammatory immune messenger substances such as cytokines, interleukin-6 and TNF-alpha can contribute to a severe course.
As a result of the secretion, inflammation and organ failure can occur in the entire body.
The immune type 1 identified by American scientists is the most unfavorable variant in the fight against the virus, because a person with this immune type has too few immune cells that can kill the virus cells, but too many immune messenger substances, which are due to their high number when released Cause inflammation.
(bb)
