Contents
Some people are not very careful or have frequent contact with people with COVID-19 and yet do not become infected. Scientists suspect that the long evolutionary path of the coronavirus may have developed gene variants that protect against infection.
- Even though the pandemic has been going on for more than two years and SARS-CoV-2 variants are increasingly contagious, some have never had COVID-19
- “Corona-resistant” is a great mystery to scientists. Research is ongoing to help understand this atypical defense mechanism. His discovery could help in the development of an effective drug
- One of the theories explaining the phenomenon of resistance to coronavirus concerns the blood group. Researchers believe that we become infected more easily if the sick person next to us has the same blood type as us
- The cause may also lie in our intestinal microflora
- More information can be found on the Onet homepage
Author: Pia Heinemann / The world
Some are crown resistant
“I am untouchable,” says Bevin Strickland on the phone, laughing out loud. An anesthesiologist from High Point, North Carolina, was helping out in New York City when the first wave of coronavirus infections hit the city two years ago.
Everything fell apart. Beds and coffins were missing. “I looked after patients in nursing homes,” says Strickland. “And that’s in Queens, where nobody has money and people often don’t speak English or Spanish,” she adds. She experienced fear of people and of death. In this situation, she couldn’t wear the mask, so she took it off. “I wanted to be with the patients,” she says. She helped intub the sick and breathed in air saturated with the virus. “I didn’t catch it until today”. Strickland still remains negative.
These and many similar reports have led researchers to argue that there are people immune to the coronavirus. They do not get sick because viruses cannot penetrate their cells or because their immune system eliminates them soon after infection. This may be due to the microbiome, the organisms that live on and in the body, the blood type, and several other factors.
This thesis is currently being tested in an international genetic research project at around 150 institutes. People like Strickland are undergoing long-term research in hopes of understanding the protective mechanism and developing drugs against COVID-19 from there.
András Spaan is an expert in genetics and infectious diseases at Rockefeller University in New York and a spokesman for the genetic research project. He says 2 people have been identified worldwide who are immune to the coronavirus. It was surprising at first. “After all, SARS-CoV-XNUMX is new, and there is really no reason to assume that humans have a defense mechanism against the virus in place.”
The rest of the text below the video.
Special variants of the genes close the “gate” to the virus
Human organisms have always struggled with pathogens. The gene variants that protect against the coronavirus may have arisen along a long evolutionary path. “We know that such protection was already being produced against other diseases,” says Spaan.
In the early 70s, the American parasitologist Louis H. Miller was able to show that red blood cells that did not have the so-called Duffy factor (surface protein) on their surface were not infected with the malaria pathogen. The absence of such a gateway to pathogens was later attributed to a special gene variant. People with it are immune to tropical fever.
Scientists are also aware of the hereditary protective factor in AIDS: HIV cannot penetrate the cells of people who carry the CCR5 gene variant. Here, too, the pathogen has no point of entry into cells, in this case immune cells.
“Once the biological pathways affected by the CCR5 variant were decoded, it became possible to develop a drug against AIDS,” says Spaan. “Of course, it would be great if we could do something similar with COVID-19.”
The fact that the SARS-CoV-2 virus cannot infect humans is probably not due to a single reason. Some people may have no or few binding receptors on the cells in the lining of the nose, throat and lungs. This means that the virus cannot or does not infiltrate it very rarely. It is also possible that their immune system is working particularly fast, or because of previous infections it has already built up basic protection and eliminated invasive viruses in the blink of an eye. Pathogens cause infections but are unable to reproduce.
Search for the untouchable
Scientists it is difficult to be sure whether someone is truly immune to the coronavirus infection or has never been infected. In addition, some people have an asymptomatic infection with no signs of disease. For those who are vaccinated, antibody tests cannot always tell with certainty whether the antibodies in the blood are due to a vaccination or an infection. And if the antibodies can’t be found, that doesn’t mean anything either: levels drop over time – if someone got infected a few months ago, the test might still be negative.
Want to check if you have antibodies to the SARS-CoV-2 virus? Reach for the simple SGTi-flex cartridge test. Available at Medonet Market.
For project researchers, this means that in order to actually recruit people resistant to the coronavirus, they had to zoom in on people who tested negative for antibodies and ask about lifestyle and exposure to infection. For example, if you’re the only person in your family COVID-19 spared – even though you all live in a small space – you had a good chance of being included in the study. Nurses such as Bevin Strickland and doctors with close and insecure contact with the seriously ill are also included.
In a study by University College London (UCL) during the first wave of coronavirus, 731 health workers were regularly checked for infections. Both PCR tests to detect virus residues and various tests were used to detect the immune system’s response to infection.
About 22 percent. nurses and doctors tested positive. This meant that 573 subjects remained negative even though they were working in the same clinic at the same time and under the same conditions.
“We looked in more detail at the T cells in these apparently uninfected individuals, which – as we know from hepatitis B and C virus infections for example – play an important role in the swift defense against viruses,” says UCL’s Leo Swadling. Those with a high concentration of T cells at the beginning of the infection did not test positive. “T cells mainly attack the replication machinery of viruses so that they cannot reproduce.”
Pathogens are “caught” very quickly. The risk of developing symptoms is correspondingly low. The theory is that prior infection with other coronaviruses leads to a rapid, high T-cell response in SARS-CoV-2 infection. Preliminary research by the Swedish Karolinska Institute, which has yet to be verified, suggests that infection with influenza viruses may have a similar effect. Here, too, protection may be due to T cells.
The role microbiome
The hypothesis that this is less explored the microbiome can influence whether and how the coronaviruses multiply in the body. However, there are indications to prove this: in seriously ill patients, scientists have often found particularly low-grade intestinal flora.
It is known from experience with other respiratory viruses that the short-chain fatty acids produced by special intestinal bacteria regulate the immune system. This has not yet been conclusively studied with SARS-CoV-2. It may well be that the infection damages the intestinal flora of patients.
One more factor may appear to protect against infection: blood type. Anyone who inhales the same air as a COVID-19 patient with a compatible blood group – i.e. A from A or B from B or A from AB – has a high risk that the virus could enter their cells. On the other hand, if blood group A meets blood group B, the risk is lower.
Scientists at the University of Nantes recently discovered this and published it in “Frontiers in Microbiology”. Thus, they solved the mystery of why people with blood type 0 have a low risk of infection in Western Europe: it is the rarest.
The genetic research group led by András Spaan is now trying to find further correlations at the genetic level and then elucidate the mechanisms involved in protection.
Bevin Strickland, a North Carolina crown-proof nurse, is cautious despite testing negative results. “I’ve been vaccinated three times and usually wear a mask,” she says. And she adds: «I work with sick people. I want to protect them ».