Long Covid is always different.

We have long since become accustomed to this observation.

A few hundred possible symptoms have already been described in the medical literature, and the suffering of the patient is almost never the same.

That alone makes a systematic approach more difficult and also contributes to the repeatedly expressed (and sometimes trivializing) conviction that Long Covid - all the pathological long-term consequences after an infection - is not yet so clearly defined scientifically.

But now there is another facet of this suffering: the virus itself can apparently also influence the long-Covid course.

Depending on which genetic variant you have been infected with, one or the other symptoms can occur preferentially.

At least that is what an Italian study with 428 Covid-19 patients suggests,

Joachim Müller-Jung

Editor in the feuilleton, responsible for the "Nature and Science" department.

  • Follow I follow

Two pandemic phases were distinguished in the study presented at the most recent ECCMID Infectious Diseases Congress: The first between March and December 2020 was the first corona wave in which the original virus, which was carried out from Wuhan, raged worldwide, the second refers to the period January to April 2021, when the much more aggressive and highly mutated alpha variant was widespread.

Many symptoms were similar, in particular the chronic fatigue syndrome (fatigue), which is characteristic of a third of long-Covid patients.

But there were also clear differences: The Covid victims who were only infected with the more aggressive alpha variant at the beginning of 2021 and who were also more seriously ill on average suffered significantly more from long-term muscle pain, confusion, depression, anxiety and sleep disorders.

Persistent odor and taste disorders, persistent breathing difficulties and hearing problems, on the other hand, were much less common with the alpha variant than with the wild-type virus from Wuhan.

It is still unclear to what extent this plays a role in newer variants, especially in omicron, which shows clear differences due to various mutations when it comes to infecting different tissue types.

The Italian long-Covid patients had one thing in common: They had all been treated for severe Covid 19 disease, many with immune disorders and the elderly had to be ventilated.

But experience has shown that Long Covid affects much more than this group of seriously ill Covid patients.

Even mildly ill and symptom-free infected people can suffer from one or more typical long-Covid symptoms weeks and months after infection.

In a new, systematic meta-analysis in "Jama Network Open", after evaluating 57 studies with a quarter of a million corona positives, it was shown once again how often long-term consequences occur: 54 percent of the patients suffered from one or more long-term Covid symptoms.

The scientific evidence comes from all sorts of countries around the world.

The extreme scatter in the severity and frequency of symptoms does not depend on geographic factors, but is an expression of the different data collections and patient selection.

In this respect, it can actually be said today that the risk of Long Covid still cannot be limited, especially not in children, for whom the data basis is much more perforated.

One thing is clear: Late and long-term consequences can affect practically every organ in which the Sars-CoV-2 system virus is able to multiply itself - i.e. throughout the body from the nervous and vascular system to the genitals - or in the The immune system, which has been severely affected in Covid-19 patients, fails or is directed against their own tissue.

The exact pathological mechanisms are not yet fully understood.

And the question is also unanswered as to what role the psyche and social circumstances play in the development of the various symptoms.

But according to the Jama authors around Vernon Chinchilli from the Milton S. Hershey Medical Center, the frequency and the long duration of the postviral diseases, which often also lead to long-term incapacity for work, are quite suitable "to overwhelm the health systems working under scarcity".