Dodging the bullet of the coronavirus is becoming increasingly difficult. A few months ago many people could be proud of not having even had contact with him SARS-CoV-2. Unless they knew. However, the current great wave caused by the omicron variant has meant that, to a greater or lesser extent, most people have been more or less exposed. Even so, there are those who are still not contagious, even having been living with infected patients. East escape the contagion of coronavirus It is a mystery to many scientists, who are already beginning to study in search of the causes. They are not yet clear; but, for now, it seems to have had a cold it could have to do with that mysterious protection.
It is the conclusion of a study that has just been published in Nature Communications, from the hand of a team of scientists from the Imperial College From london. In their study they point out as responsible for this cross protection some very important soldiers of our immune army: the T lymphocytes.
These are cells that recognize a pathogen and attack it, but with the difference that they remain in our body longer than antibodies. But what does all this have to do with cold?
Saved by the cold
Although we know the cause of COVID-19 as THE CORONAVIRUS, the truth is that there are many coronaviruses. Are their cousins more ferocious, causing in the past of the mortals SARS and MERS epidemics. But there are also other quite milder ones with which we are constantly in contact and that, in general, do not cause more than a cold.
It is not the same virus, but the relationship it maintains has led to, as previous studies had shown, the T lymphocytes who recognize some may also recognize others. But just because they recognize them doesn’t mean they can attack them. This is something that was not known until now, hence these scientists have focused their research on trying to find out.
And for this, the best way was to have those people who seem to dodge again and again the contagion of coronavirus. People who, even living with the disease, have passed without being infected.
To carry out this study, 52 persons who lived with COVID-19 patients. Half of them had fallen ill as well, while the other half evaded the contagion of coronavirus.
The study was conducted in September 2020, when most people in England had not been infected or had not received any of the coronavirus vaccines. Thus, if there was prior immunity, it must be for another reason. In fact, none of these patients had antibodies indicating a previous SARS-CoV-2 infection.
All of them had a PCR on the day of detection of the positive of his companions and also 4 and 7 days later. In addition, blood samples were taken during the first 6 days of exposure to the virus.
Thus, it was seen that those who did not get sick had higher levels of T lymphocytes targeting others in their blood. cold-causing coronaviruses. There was, therefore, a cross immunity. His immune system detected SARS-CoV-2 and fought it off, so to speak, because it mistook it for a relative it had already fought before.
The authors of this study believe that what they have discovered may be useful even for the development of new vaccines.
The causes are clear. The protein spike it is that key that SARS-CoV-2 uses to infect our cells. But it is also the red flag that normally attracts the immune system. The antibodies that are generated before a first exposure or before vaccines are directed at it, causing great pressure against the virus that can drive the evolution of mutations that escape them. He has explained it in a release the teacher Ajit lalvani, lead author of the study.
The proteins to which T lymphocytes target, on the other hand, are much less exposed. If we visualize the virus as a human being, we could say that the spike are the arms and the proteins that recognize the T lymphocytes the heart. Being less exposed, it is more difficult to attack them, but it is also more difficult for their mutations to thrive into new variants. In short, they are much more conserved between different variants. Even in the omicron. And that could be very useful to prevent the spread of the coronavirus with new vaccines.
In any case, it does not seem that this is still necessary, since the vaccines that we currently have, to a greater or lesser extent, protect us from becoming seriously ill from COVID-19. For this reason, the authors of this study emphasize that, although the cold can give us some protection, the safest thing is to have the complete vaccination schedule. If we add to it the cross protection that a cold offers us, all the better, but we shouldn’t gamble on that card alone.
On the other hand, the study authors also acknowledge that their research has certain limitations. To begin with, it has been done with a very low number of participants. And furthermore, they were all from European white ethnicity, so other geographic origins are not taken into account.
It is only a brushstroke, yes, but it helps us to see one of the channels by which some people are avoiding the contagion of coronavirus. But no, if you have recently had a cold that does not exempt you from getting vaccinated. Nor does it give you carte blanche to go without a mask for life or to lead a normal life if you have symptoms. The cold can help you, but if you are not vaccinated, you are at the mercy of the COVID-19. We have already seen what it can do. The best option is not to risk it.