I have enough of a background in science to be able to follow some of the discussion around what Covid does and how the vaccines work. Its a challenge to communicate things well to a lay audience while maintaining scientific accuracy. One young researcher who is doing a great job is Dr Rob Swanda, who has recently completed a Ph.D on using m-RNA for other medical applications. Rob has posted a series of informative short videos on Youtube and his blog. As someone who has spent time developing educational materials in science I can only applaud his efforts!
https://www.drswanda.com/videos-english
One common accusation by anti-vaxxers is that the vaccines were 'rushed' or developed 'too quickly'. However a number of factors really helped to speed the vaccine development.
Firstly, researchers were able to physically isolate Covid-19 virus from humans affected by the disease. There are electron micrograph photos of virus particles emerging ('Alien-like') from smashed-up cells they've infected - look for the picture credited to Dr Katherine Davies on this page:
https://www.nature.com/articles/d41586-020-00502-w
Secondly, biochemists at the University of Texas were able to completely map the details of the spike protein and see where it attaches to human cells. See the picture credited to UT Austin, McClellan Lab on this page:
https://www.nih.gov/news-events/nih...structure-reveals-targets-vaccines-treatments
and note that the structure was published as early as February 2020. The researchers spotted that the green strand at the top of the spike in that picture is the point of attachment and that was then an obvious target for the vaccine. All three vaccines approved in the UK work by covering that 'binding site' and reducing the amount of infection. Of course if you get a high 'viral load' (e.g. lots of virus) that may not be enough to give you complete immunity but it will greatly reduce the risk of death/hospitalisation.
On the 'delta variant' the vaccines still cover the protein spikes, but any virus particles that evade the vaccine are particularly good at reproducing themselves. So you may end up with a high viral load and become more ill than with the previous variants. It doesn't mean that you shouldn't take the vaccine though - it means that you really, really, should take it if Delta is around. One of the Swanda videos talks about Covid mutations:
Ooops, this comment turned out longer than I thought - hope its still useful!