Handy mnemonic device in case you don’t have time to read through when shit gets real:
Orange = normal human flesh. No worries.
Red = blood. Remain vigilant.
Green = zombie flesh. Time to panic.
Black = death. World’s basically overtaken. Sorry.
Everything is pretty much okay. If there are zombies roaming the streets, they’re far enough away that you can go about your day as usual.
Zombies are officially a national concern. At this point your fight-or-flight response should be kicking in. If you don’t have a contingency plan, it’s time to get on that.
Full-on zombocalypse. Zombies outnumber humans on an international level. Your only option now is to try and wait them out and hope enough humans are left later on to repopulate the planet.
Everyone’s dead. Either you’re one of the handful of humans left huddling in a basement somewhere, or zombies have evolved and can now browse the internet. I’m betting on the former.