Good points, but I have to say that at least the summary article smells of reductionist science to me. It's both "water is wet" and "water is the only way to pu

Good points, but I have to say that at least the summary article smells of reductionist science to me. It's both "water is wet" and "water is the only way to put out a fire" at the same time. Even if there is a "statistically significant" correlation between (lack of) this particular marker and breakthrough infection, it is still at least as possible that immunity requires a coordinated response from several parts of the immune system, with no part particularly dominant. A weaker response by one part could be compensated for by another part. If you're not good at neutralizing the virus but you're really good at preventing it from entering, you may be just as ok as someone with opposite strengths. Another way to say that is that there very well might not be a relevant threshold of this one marker, or the threshold may be so extreme as to be uninteresting. We might need to combine additional markers. (I really ought to read the actual study before nitpicking on its reporting, though.)