Current Any% WR has no info on which type of plague they used, I personally think this means there should be separate categories for each type of plague.

That is the individual level leaderboards. The any% can be any disease as the goal is to just be as fast as possible (without cheats). Any disease goes

Nano Virus

isn't any% completely pointless since it's just the fastest IL

It's not. any% was Neurax Worm once upon a time.

i... don't see how that's relevant?

any% can change as new strats are found. maybe one day we will figure out we can kill the world in 40 seconds with virus, it all depends on how we start to learn about the game