In this thread, none of the comments seem to note a key issue here as stated in the FDA post: "Those participants who did not receive two vaccine doses at either a three-or four-week interval were generally only followed for a short period of time, such that we cannot conclude anything definitive about the depth or duration of protection after a single dose of vaccine from the single dose percentages reported by the companies. "
In other words, we basically have NO DATA on single dose schedules for Moderna/Pfizer vaccines. There's too few of them anyway to gain any statistically meaningful insight even if we did follow up on these study participant washouts. This is hydroxychloroquine all over again. When you are looking at inadequate data, you can find all sorts of patterns. It is very rare that such patterns turn out to be real. The most reasonable approach is to assume that there is little to no durable protection from a single dose, just like most prime/boost vaccines.
In other words, we basically have NO DATA on single dose schedules for Moderna/Pfizer vaccines. There's too few of them anyway to gain any statistically meaningful insight even if we did follow up on these study participant washouts. This is hydroxychloroquine all over again. When you are looking at inadequate data, you can find all sorts of patterns. It is very rare that such patterns turn out to be real. The most reasonable approach is to assume that there is little to no durable protection from a single dose, just like most prime/boost vaccines.