Scientists postulate that if someone combined rabies with an airbone influenza, it would create the equivalent of a rage zombie virus. Check out this article from National Geographic:
A faster mode of transmission would be through the air, which is how theinfluenza virus spreads.
“All rabies has to do is go airborne, and you have the rage virus” like in 28 Days Later, Max Mogk, head of the Zombie Research Society, says in the documentary. The international nonprofit is devoted to “raising the level of zombie scholarship in the Arts and Sciences,” according to their website.
To be transmitted by air, rabies would have to “borrow” traits from another virus, such as influenza.
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It’s theoretically possible—though extremely difficult—to create a hybrid rabies-influenza virus using modern genetic-engineering techniques, the University of Miami’s Andreansky said.
“Sure, I could imagine a scenario where you mix rabies with a flu virus to get airborne transmission, a measles virus to get personality changes, the encephalitis virus to cook your brain with fever”—and thus increase aggression even further—”and throw in the ebola virus to cause you to bleed from your guts. Combine all these things, and you’ll [get] something like a zombie virus,” she said.
“But [nature] doesn’t allow all of these things to happen at the same time. … You’d most likely get a dead virus.”
The National Geographic Channel has a special titled the Truth Behind Zombies. This can’t be good 😉