I was told the first Pfizer shot takes weeks to kick in but the second shot only takes days.
Yes but I also hear the longer the weeks wear on, the stronger the protection from the first one...just on its own. So getting the second shot later as opposed to too soon could be even more of a boost than would otherwise be?
The clinical trials implemented 3-4 week waits because that’s all they had time for.
As I said, should depend on age and co morbidities of person receiving shot.