I think in practice, the prescribing doctor makes the decision when he or she decides to write the prescription; I can't imagine a pharmacist refusing to fill a prescription.
My point was that previously no prescription was required for most vaccines, including the COVID vaccines. The matter was left to pharmacy, insurance and patient. Will these new restrictions now require a trip to MD? How tightly will they enforce ‘pre-existing health condition’?
Jerome Adams actually answered my question on this - but the answer was that it will depend on rulings that have not happened yet.