Is The Walking dead part of the BB universe?
They had blue meth in it.
shareThe blue meth is what turned everyone into zombies. It was all Walt and Jesse's fault.
Supposedly it was someone who tried cooking the blue meth after Walt died that didn't follow the recipe that caused the zombie virus.
But exactly how that would affect non-meth users is beyond me.
Ordinary meth causes "meth mouth", where your teeth rots.
Blue meth causes full-body rot, where your entire body rots, turning you into a zombie.
If you're bitten by a late-stage blue meth user, the trace amount of blue meth in his saliva is enough to begin the body-rotting process in the bite victim, like how merely touching pure fentanyl powder can cause you to overdose. That's how the non-meth users are affected.
Meth users are a very small percentage of the general population in any given area ( with some exceptions limited to mostly small rural areas), & even less so on a global scale.
Also, they tend not to interact with non-meth users.
And since Jenner had told Rick that everyone is infected, I still don't see how such a small number of blue meth infected could infect the entirety of the world populace.
Unless, somehow, residue from the blue meth &/or the cook process itself got into the entire air/water supply world-wide.