What mutations are there?
Short answer: very many.
In fact, around 12,000 mutants / mutations of SARS-CoV-2 are registered worldwide. However, so far only a few have developed in such a way that they give the pathogen selective advantages and accelerate the course of the pandemic.
The British mutation B.1.1.7, the South African mutation B.1.351 and the Brazilian variant P.1 are so-called questionable variants (Variants of Concern, VOC for short).
Overview on the subject of coronavirus (imago / Rob Engelaar / Hollandse Hoogte)
How common are the different mutations?
It is not that easy to get a clear picture of the proportion of mutants in the positive tests. Because for a long time Germany failed to examine the samples for this. However, the sequencing of the virus genome required for this is also complex and can only be carried out in special laboratories. In the meantime, however, the RKI has established a test number recording system in which more and more laboratories are participating. Since the beginning of February, the institute has been publishing these secured analyzes broken down by calendar weeks.
The British variant in particular is spreading rapidly. According to the Federal Minister of Health Jens Spahn, more than 20 percent of all new nationwide infections can be traced back to the mutant B.1.1.7. Studies by the Robert Koch Institute (RKI) from four different data sources paint a similar picture.
The percentage increase compared to the previous weeks is particularly noticeable. In the fourth calendar week, only about five percent of all positive samples could be assigned to mutation B.1.1.7, in the following calendar week the proportion was already about eleven percent.
The evaluations by the RKI also show that variant B.1.1.7 has already been verified in all federal states.
The number of South African and Brazilian mutants, which has so far been rather small, is growing somewhat more slowly.
What are the dangers of mutations?
Of the three variants mentioned, it is known, among other things, that the structure of the so-called spike protein has changed. With this protein molecule, the virus docks onto the surface of body cells and gains entry. In this respect, figuratively speaking, the mutations have an improved key and thus reach human cells more quickly and more effectively.
The professor for clinical pharmacy at Saarland University considers an incidence value of below 20 to be sensible and warns of the virus mutants.
Lehr anticipates an increase in the number of infections due to the new virus variants from mid-March and is based on simulation calculations from the CoSim project.
What does it mean when the proportion of mutants increases?
The pharmacist Thorsten Lehr emphasizes that the simulations already include the current continuation of the lockdown. “And it will be even more frightening if we then introduce a certain degree of relaxation, then we would see a re-entry very quickly. And that must of course be prevented exactly.”
Dlf science journalist Volkart Wildermuth emphasizes: “For individuals it doesn’t matter which variant they are infected with, the risk of a severe course remains the same. But socially it makes a big difference whether a virus spreads faster.
The n it takes hold the countermeasures are no longer so good. “
What are the consequences of more infectious variants?
Mutations change a crucial parameter of the model calculations: the risk of infection by the virus. Science measures it in the so-called reproduction value R. It indicates how many people an infected person infects on average. If the R value is below 1, the infection process gradually weakens; if the R value is above 1, it increases.
The falling number of infections since the beginning of the year had shown that the current restrictions could depress the previously prevalent wild type of the virus. However, this no longer applies if the proportion of more contagious variants such as B.1.1.7 increases.
Currently, the R value does not differentiate between the different virus variants, but rather determines an overall picture. If the spread of the mutant B.1.1.7 continues to the same extent as before, incidence values of 175 could be reached as early as the end of February, as the biologist and physicist Cornelius Römer determined for the “Tagesspiegel” – but then with significantly more contagious viruses .
With the numbers increasing rapidly, health authorities are increasingly unable to guarantee contact tracing. One consequence is that infected people are isolated too late or not at all. Because more members of risk groups are then very likely to become infected, the number of intensive care patients and ultimately the number of fatalities also increases.
(dpa / dpa-Zentralbild / picture alliance / Bernd Wüstneck)Intensive care physician about corona mutant
Despite the falling number of infections, the lockdown was extended. That’s right, believes the intensive care doctor Christian Karagiannidis.
“We fear, based on what we have calculated with our forecast models, that the British mutant in particular will catch on very quickly and that we will then probably get another significant increase in the number of patients in April, May and June,” said intensive care doctor Christian Karagiannidis on Deutschlandfunk.
How effective are previous vaccines against the mutations?
The AstraZeneca vaccine is said to offer only “minimal protection” against mild and moderate disease courses. “Those who have been vaccinated can become infected and then develop symptoms,” explains the Dlf science journalist Volkart Wildermuth, adding: “But they still seem to be protected from a serious illness.”
(picture alliance / Jochen Tack)Vaccines and their effectiveness
So what do the corona vaccinations do? And how do they work against new variants of the virus?
The vaccine from BioNTech / Pfizer, on the other hand, is said to be effective against both the SARS-CoV-2 mutations that have appeared in Great Britain and South Africa. Corresponding data on the study were published in the journal “Nature Medicine”. Moderna also reports that the variants are highly effective.
The central component of most vaccines is genetic information – and this can be changed relatively easily, i.e. adapted to new mutants. Almost all known vaccine manufacturers are already working on it.
Do high case numbers lead to even more dangerous mutations?
According to the current state of research, this can be assumed. Strictly speaking, high incidence values in combination with initially low vaccination rates act like a kind of incubator for mutations. “If you vaccinate a population in which a lot of the virus is circulating, the virus comes under pressure.
The re is a growing risk that further mutants will emerge, even more unpleasant than the British, Brazilian, and South African variants. So it is also a question of getting the vaccines protect and keep the incidence low, “says the weekly newspaper” Die Zeit “.
(picture alliance/dpa/ Kira Hofmann)“Zero Covid” und “No Covid”
What are the differences and what are the similarities between the two concepts?
In order to ensure the success of the vaccination campaign and to prevent the development of dangerous mutations, the number of new infections should be kept small. An interdisciplinary group of European scientists is proposing the so-called no-covid strategy.
The group’s approach is to achieve an incidence of less than 10 per 100,000 inhabitants per week across Europe. This requires steps such as consistent testing, seamless tracking of the chains of infection and restrictions in mobility.
Sources: Dlf, RKI, Volkart Wildermuth, Tagesspiegel, Die Zeit, jma