The Virus mutations also provide opportunities
The Coronavirus SARS-CoV-2 is constantly changing, such as other viruses also. This process is called Mutation and is an important part of the Evolution. Under a mutated Virus, most people imagine a pathogen that is more dangerous than before. However, this process can also lead to a Virus is less deadly. A virologist explains why SARS-CoV-2 could be in the course of time to a harmless runny nose.
Professor Dr. Christian Drosten is head of Virology at the Charité – Universitätsmedizin Berlin and a specialist in the area of corona viruses. In the NDR Podcast Coronavirus-Update the expert on how viruses mutate and what impact this may have explained. In the case of SARS-CoV-2, the chances are good that the Virus is due to mutations less dangerous.
Viruses are subject to constant change
Many types of viruses are constantly changing. Alone of the Influenza Virus, which provides each year for flu-shaft, exist in three main types and many subtypes, which is why the vaccine is also constantly needs to be changed and not a hundred percent protects.
The Evolution of viruses
An infected Person forms a Virus Population within the body. This Population can also include a portion of mutated viruses, or new mutations within this Population. The mutations are purely random, and in most cases they offer no advantages for the Virus, which is why they disappear with time. In General, mutations provide only an advantage, if, in a Generation of mutant viruses, once again, a Mutation is performed.
“It is often in Evolution that a Mutation makes no difference and the sum of three, four, or five mutations, the power to a large phenotypic change, i.e. in the shape and forms of appearance and the behavior of such a Virus,” says Drosten.
If mutations are at a selective advantage
That such a Mutation happens within a single Person, is extremely unlikely. If a Person is infected, however, a different Person, there will be always only a small part of the total virus population. This part can also already contain mutant viruses. This mutant part meets population to another mutated part of the population, it can come Drosten, according to a huge selection advantage for the Virus. A Generation is given the mutations that have arisen in two different sub-populations. “And this, together the mutations are stuck, this is recombination, so the Cross each other and melting together of Genomes,” says the virologist.
Evolution is a pure coincidence.
“This is simply Evolution, it just happens”, says the Coronavirus expert. This is no idea or no Plan put. If a Virus is altered randomly so that it can reproduce better, or spread, than the Original, then the new Virus displaced the old over time.
Mutations are harmful for the people?
“I don’t want to say that we must fear something,” emphasizes Drosten. However, you must remember that the Coronavirus SARS-CoV has 2 very good chances, through Mutation, to be adapted to humans, because the Virus is transmitted in a large propulation size, so that mixed compositions of mutated viruses can be Infected over there. This increases the probability that mutations converge, cause a selective advantage.
The changes in SARS-CoV-2 to imagine?
Recently, a current study showed that the Coronavirus SARS-CoV-2 increased the fastest in the nose and the nasal cavity is likely the primary entry point for the Virus. A selective advantage for SARS-CoV-2 mutations could be that the Virus is specialized to better the nose. “But in the nose, we are not too sick of it,” explains the Coronavirus specialist. Specifically: COVID-19 could be in the long term, to a cold, spreads into the lungs. “Something could happen”, underlines Drosten.
Dangerous mutations do not necessarily provide a selective advantage for the Virus
For the people significantly worse option would be that SARS-CoV-2 enhances skins by mutations propagating potential in other mucus. This would make the disease more dangerous, because the risk for infection of the lungs increases. But Drosten holds the first case is more likely. “If a Virus is focused better on the nose and less in the lung sick, then we may run for a long time with a runny nose through the area and we feel not sick at all,” says the virologist. In this case, the Virus would spread faster and would have a selective advantage.
If there is a more dangerous variant is rampant, people are more cautious and are more likely to stay home and it be carried out more measures to contain it. As a result, the Virus is transmitted less probably to other people, which is not a selective advantage for the Virus. “And now I’m going to Drosten from the evolutionary biologists to the people, says again, cautiously optimistic that I believe that this is one of the drivers, the causes of experience are in accordance with the actual virus epidemics over time, harmless,” says. (vb)
Also read: Coronavirus spread: nose COVID-19-course of a disease.