Corona theories by researchers: who gets caught, who gets spared

  • Sven Trautwein

    OfSven Trautwein


Many people are infected with the corona virus when they first come into contact with it. Others are not infected. Researchers have various explanations for this.

Munich – For some, an infection with the corona virus looks like a gamble. While those who have been boosted are infected again when they first come into contact with Covid-19, others are almost completely spared. Researchers around the world have collected data and developed hypotheses about what might be causing it.

Corona: Four theories that speak for or against an infection

Researchers’ corona theories: who gets caught and who is spared. (icon image)

© Photobooth/IMAGO

Many people are still ending up in intensive care units around the world, although classes are generally milder than at the start of the pandemic. Virologists and immunologists are still puzzled as to why some people are infected with corona, even multiple times. Others who have been in contact with infected people themselves do not get sick. Looking at the collected results, four theories have emerged.

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Corona infection: Scientists pursue these theories

Although many things still seem unclear, scientists have come up with these theories:

  • Vaccinated people have already been infected without being noticed.
  • Genetic differences are crucial, especially blood type.
  • The immune system works differently.
  • The immune system depends on the time of day.

Corona theories: unnoticed infected and the immune system

It has often happened to people who have been vaccinated three times to be infected without being noticed. It couldn’t be completely avoided. However, the viral load is so low that a rapid test does not work. People experience no or only very mild symptoms similar to a runny nose.

The immune system is different from person to person. Some people’s immune systems work better than others. Researchers are seeing evidence that defense cells built over life are more effective against novel corona viruses and thus offer better protection.

Corona: What role do blood type and time of day play?

Our immune system fluctuates from day to day. When we feel rested and relaxed, the attacking viruses often have a harder time doing anything. However, if we are not as resilient due to previous illnesses or lack of sleep, the coronavirus is more likely to multiply in the body and cause harm.

Here too, researchers are interested in genetic differences. So far, about 15 gene segments have been discovered that influence our immune system. The part of the gene that determines blood type is of great interest. It seems that people with blood group 0 are less likely to be infected with the corona virus. French researchers have concluded that this group is more difficult to infect, but can transmit infection very easily.

Professor Carsten Watzl from TU Dortmund also recently commented on why some get Covid and others don’t. This topic should occupy researchers around the world for some time. After evaluating many data, an infection is also dependent on the viral load. Masks and distance continue to offer the best protection here.

This article only contains general information on the respective health topic and is therefore not intended for self-diagnosis, treatment or medication. It does not replace a visit to the doctor. Unfortunately, our editors are not authorized to answer individual questions about clinical images.

List of headings: © Fotostand/IMAGO

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