We have antibodies in our blood that are produced in response to an infection. If the infection tries to attack again, then these antibodies will block it. Usually these are the so-called class G immunoglobulins.
And we also have special class A antibodies for mucous membranes on our mucous membranes. They are in our nose, mouth, throat, lungs, intestines and various other places where mucous membranes come into contact with the environment.
Such secretory antibodies are transmitted by the mother to the child. with breast milk, and in the child, his mucous membranes become more protected.
And now (attention!) A question. Can a person who has recovered from some kind of infection exhale antibodies from their lungs that would protect the people around them from this very infection?
Well, like the one who has recovered is no longer contagious. If he sneezes, his antibodies from the respiratory tract will fly into the air and fly into the nose of another person and protect him from infection. Is it logical? It is logical.
Let's follow a simple logical path. On the surface of the respiratory tract in the very mucus that we cough up, swallow or spit out, there are antibodies that can fly out with drops of this mucus.
Drops are constantly flying out of people. They fly out not only when coughing and sneezing, but even during normal conversation. This is how infections are transmitted from one person to another. This is how antibodies can fly into another person along with drops. But only I very much doubt that this amount of antibodies will save anyone.
There were such studies when unfortunate mice were infected with an infection and human antibodies were sprayed into their respiratory tract. So it was possible to protect the rodents from infection.
So the idea is interesting, and the desire to take off the masks is understandable. Only it won't work. A woman who is ill can pass antibodies in milk. But with drops of sputum, they are usually not transmitted.