[tdrdt]

There is no difference between what is injected.

It's more like a retraining program. It's almost like the difference between short and long term memory. One shot will turn on short term memory after a week or two. Repeating shots will turn on long term memory.

But what I personally think is interesting is that a natural infection works longer and broader after just one 'dose'.

It is amazing how complitacted the immuunsysteem is. And I also think this is the reason we should be careful with giving healthy young people the vaccins.