I occasionally meet people who claim they’ve never been sick, or, sometimes, that they’ve never had a cold.
I don’t buy it. There’s more than a whiff of brittle insistence in these claims.
But has there ever been a documented case of a human being who appeared to have some sort of significant immunity to all ~200 viruses that cause colds?
I’m not a physician or microbiologist, but given my (limited) understanding of the human immune system, this seems exceedingly unlikely.