There are many differences between the 'zombies' of Rage Virus aren't technically dead - but one bizarre similarity reveals that both conditions enhance the human body in a surprising way.
In The Walking Dead, Rick Grimes' band of survivors contend against hordes of the risen dead, with every person in the world afflicted by a mysterious condition that resurrects them from death as a shambling predator. In contrast, 28 Days Later is far more explicit about the cause of its outbreak, as Danny Boyle's 2003 movie sees an infected lab animal set free, spreading a violent rage across the populace of Great Britain. The Rage 'zombies' are fast and self-destructively violent, mostly hunting at night, while Walking Dead's Walkers act more like a natural disaster, gathering together in huge groups that are unstoppable due to sheer numbers. However, both types of zombie ultimately hunt using the same ability.
This shared ability is a surprisingly enhanced sense of smell, with both franchises establishing that their zombies differentiate between humans and their fellow undead by scent. This is shown most prominently in The Walking Dead #4, where Rick and Glen are able to move among the Walkers without being attacked by covering themselves in zombie matter. This masks them from the zombies, and even allows them to talk and demonstrate other signs of life without being attacked. In The Walking Dead Deluxe #4 - from Robert Kirkman, Tony Moore, and Dave McCaig - Kirkman notes that while this was a new addition to "Romero-style zombie mythology," it doesn't make much sense for his personal brand of the undead, saying:
Does this theory make any sense? Not at all. Zombies' nervous systems work somewhat, that's how their brain is still sending signals to their body, but their respiratory systems are very much not working. They walk around underwater just fine. They don't need to breathe. So how do they smell without breathing in? What?! You know what... still cool. I stand by it.
This ability is hugely dialed up in the world of 28 Days Later. In the comic 28 Days Later: The Aftermath (by Steve Niles, Dennis Calero, Diego Olmos, Ken Branch, and Nat Jones), it's established that its zombies can't just smell the difference between each other and uninfected humans, but that this is how they hunt. When two armed survivors end up battling for territory over the rooftops of London, the winner triumphs by dumping perfume on his opponent, guaranteeing that every zombie in the area will smell it and instantly converge on his rival.
While zombies are often depicted as being stronger than anyone would expect of a living corpse, it's rare that they're depicted with other physical enhancements, however both 28 Days Later and The Walking Dead choose to give them a surprisingly sophisticated sense of smell. Sadly, this fact goes relatively underexplored in both franchises, but in a world where A Quiet Place and Bird Box fascinated audiences with predators who operate by a specific sense, maybe the next zombie epic will build on 28 Days Later and The Walking Dead's example and experiment with the possibilities of a world where the cannibalistic undead hunt by scent.
