Is the Delta variant a result of COVID evolving against the vaccine or would we still have the Delta variant if we never created the vaccine?
This answer is from an immunologist.......
Delta arose in India when vaccination levels there were extremely low. Delta has only slightly increased vaccine resistance relative to the earlier strains of SARS-CoV-2. And delta has greatly increased transmission capacity.
So delta arose in the absence of vaccination, doesn?t do much to avoid immunization, and has obvious selective advantages unrelated to vaccination. So yes, the delta variant would still be here if there was no vaccination. In fact, if vaccination had been rolled out fast enough, delta (and other variants) would have been prevented, because the simplest way to reduce variation is to reduce the pool from which variants can be selected - that is, vaccinate to make far fewer viruses, making fewer variants.
This answer is from an immunologist.......
Delta arose in India when vaccination levels there were extremely low. Delta has only slightly increased vaccine resistance relative to the earlier strains of SARS-CoV-2. And delta has greatly increased transmission capacity.
So delta arose in the absence of vaccination, doesn?t do much to avoid immunization, and has obvious selective advantages unrelated to vaccination. So yes, the delta variant would still be here if there was no vaccination. In fact, if vaccination had been rolled out fast enough, delta (and other variants) would have been prevented, because the simplest way to reduce variation is to reduce the pool from which variants can be selected - that is, vaccinate to make far fewer viruses, making fewer variants.
