One of the first "promises" (agility) of mRNA turned out to be a bit of a mirage.<p>We have this wonderfully adaptable mRNA vaccine technology - but we've backed ourselves into a corner re: COVID-19 because it seems "original antigenic sin" is a stubbornly real effect in this context. All current research points to updated vaccines inducing largely the same old immune response - they are not more effective than just dosing again with the original shot.<p>So we can "reprogam" the <i>vaccine</i> but getting the immune system to do something different turns out to be more difficult.<p>Where it get interesting at a population level is that nearly everybody now has these antibodies for the original spike. At a population level this seems less robust than natural immunity[1], which would have induced (again at the population level) a broader range of immune responses from sites all over the virus. You also would have had a population where some people were exposed to original, some to delta, some to omicron etc, again leading to greater antibody diversity.<p>In general, monocultures tend to be less resilient to "exponential attacks" than more diverse systems.<p>While public health authorities have repeatedly dismissed this concern, I still find it hard to believe this kind of "antibody monoculture" isn't going to have an effect on subsequent evolution of the virus.<p>Mass vaccination was almost certainly the right call from an immediate public health perspective but I can't help but feel it's also left us more vulnerable in some difficult-to-predict way for the long term.<p>[1] Agree, it's bad terminology but everyone understands it. It's all "natural" immunity, of course.