It's not a 'vaccine'. That is the lie.
You've just upgraded yourself to Transhuman Level 1. 2nd Dose is Level 2.

Don't go around the unvaccinated or you will shed your nano bots all over them and infect them too. But with now well over a billion injected, us clean folk are going to have a very rough time staying that way....

You probably don't know about 'Shedding', but if you do, try not to shed on clean people. Simple science, and common decency.

Good luck with your new body.