Mike4 wrote:The human immune system seems to struggle with the common cold. If it was that good, I'd have thought we would no longer catch colds once we've caught all the basic variants.
I suppose it depends on what you mean by "struggling with the common cold". I'd say that the human immune system actually does a pretty good job with the common cold in that while many people get it, sometimes multiple times a year, relatively few people die from it - which takes us right back to a common debate (I would be tempted to say deceit) about the Covid-19 vaccines. Some people - most antivaxxers - insist on stating that the vaccines don't work by citing the fact that vaccinated people can still get infected but ignoring the fact that the vaccines, for most people, significantly reduce the risk of a SARS-CoV2 infection become serious or even fatal.
I'm not an expert but from what I've read I get the distinct impression that it's probably true that immunity acquired via a natural SARS-CoV2 infection does confer broader-based immunity since, as Ashfordian said, the immune system gets exposed to epitopes derived from all of the viral proteins whereas after vaccination with any of the currently approved Covid-19 vaccines that I am aware of the immune system is only exposed to epitopes derived from the SARS-CoV2 spike protein. That's not to say however that the vaccines are worthless because of that, and it's also not true to say that their benefit wanes within 2 or 3 months because that is only looking at antibodies whereas T-cell responses are much longer lived and those T-cell targets (epitopes) are also much better conserved across the mutated strains that we have seen so far even if only looking at spike-derived epitopes.
As a (to the best of my knowledge) healthy 64 year old I now find myself thinking that maybe the key long term benefit of my Covid-19 vaccinations (an initial 2 dose AZ course plus a single Pfizer booster) is that, because of the protection against serious illness or death that those vaccines gave me, they offered me a safe way to catch SARS-CoV2 and expose my immune system to the full range of SARS-CoV2 epitopes beyond just those derived from spike which I hope now gives me the best broad based immunity that I can get and will allow me to fight off the inevitable future infections in a world where SARS-CoV2 is now endemic.
- Julian