“Look at the flu analogy. There is strain A, strain B. If you have been vaccinated for such strains, this does not mean that you will not catch another strain (...) Today we do not know how many strains exist- one, two, seven. Some data say that seven strains are already circulating in the world, according to other data there are already 30 strains, there is a constant mutation of the pathogen. In this situation, until we clarify the situation, scientists will not be able to clearly say how many pathogens circulate in us, then we will be able to determine whether we have protection against all strains or only against one strain," he said.
He noted that some people may have weak immunity.
“As of today, I do not know how much immunity has developed after an illness, but there are people who have immunodeficiency. They do not develop immunity, not only against the coronavirus, but even, for example, measles," he added.
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