It is known why many people go through kovid 19 easily and without symptoms, and some get the disease literally in a couple of days. There are several factors.
The first is acquired immunity to groups of similar viruses that cause colds and get sick several times a year. It is characteristic for children, young parents who have small children, people who work with children. This immunity is very important but lasts only a few years. That is why someone who grew up does not have that immunity, even if he became ill in childhood, and therefore close, in time, re-exposure to related corona viruses is needed.
Another factor is the amount of specific T lymphocytes that individual people have. We have not all adjusted our immunity in the same way, so that those who developed and directly or indirectly strengthened their T brigades over the years are now more ready for reckoning (so someone with 35 may not have them and be in danger and someone with 85 will have them and pass easily. ). These specific lymphocytes are a very powerful part of immunity not only for viruses, but we do not have them all equally, which depends not only on genetics but also on lifestyle. For example, people who promote autophagy in the body have a very large number of similar lymphocytes and other cellular mechanisms for removing excess organic particles in the body.
The third factor is silent immunization. For example, a man who took protective measures but still lived (especially in a large city where there is a large fluctuation) came into contact several times with small amounts of viruses (on contact objects, aerosols, etc.) that were not suitable to cause infection but were the organism recognized and slowly built a specific immunity, especially by building a T brigade, but also a little antibody (which is rare because they develop only with stronger inflammation as an additional defense). While, someone who has never come in contact with the virus and goes to a party where he suddenly picks up a large amount of the virus is in great danger (this is a situation with small places where you do not have a lot of fluctuations and the possibility of creating quiet immunity).
The fourth factor is genetics, some are more resistant to viruses, some to bacteria, some to both, which leads us to the fact that immunity should be nurtured for a lifetime. Proper diet, physical activity, positive attitudes, taking natural supplements (propolis, oregano, garlic, olive oil, lemon ().
And fifth, many do not even know that they have hidden diseases that take away a lot of strength in the body, that is, the body loses a lot of strength to heal them without us even being aware of it, so it suffers from immunity (multiple sclerosis, pressure, diabetes, various inflammatory processes). .).
The combination of all these factors leads to whether you will overcome this vicious disease, as well as all other diseases, on your feet.
This is the only answer that is correct.