It would be interesting to see if we can get some case control studies in the future with any future individuals who've had two vaccines and ended up getting severe infections/hospitalisations and identify if there are certain strains that will still wreaking havoc despite the inoculation to guide what to use as immunogen when we inevitably tinker around to update the vaccine. Perhaps maybe something to consider even with the single jab patients who are falling ill.
Also the clinical correlation to low neutralising antibody titres with infections or severe disease remains to be seen. I'd be inclined to presume so since the inverse *seems* to be true but who knows.
Also this interesting bit, possibly more optimistic bit, regarding T-cells
News today that Moderna is working on a variant-targeting "booster" jab
https://www.nbcnews.com/science/sci...er-shot-targets-south-african-variant-rcna310
https://eu.usatoday.com/story/news/...vid-vaccine-address-virus-variant/6802803002/
Yeah, science!