Quote Originally Posted by az city View Post
The recommended gap between mRNA (Pfizer ad Moderna) vaccines is 4 weeks. This is what the CDC has in its directives. This was the regimen used during the vaccine testing phases. It's the same across all states. There may be some variation across states based on the roll outs.

I think the UK change to an 8 week gap for AZ was based on trying to get a first shot out to as many as possible and not based on the clinical trials (which I think was 4 weeks).
It was a 12 week gap and applied to all vaccines - not just AZ. You are right about the reason for the change from the trial gap.

Earlier this year the NHSCovid app was launched for people to book vaccine appointments online - and there was a fixed 12 week gap between the first and second (and it prevented anyone booking just a first jab - to complete the online appointment booking both dates were needed). Appointments arranged via GPs were a bit more flexible. Now it is 'walk in'.