Though dead humans can't come back to life, certain viruses can induce such aggressive, zombie-like behavior, scientists say in the new National Geographic Channel documentary The Truth Behind Zombies, premiering Saturday at 10 p.m. ET/PT. (National Geographic News is part of the National Geographic Society, which part-owns the National Geographic Channel.)
For instance, rabies—a viral disease that infects the central nervous system—can drive people to be violently mad, according to Samita Andreansky, a virologist at the University of Miami's Miller School of Medicine in Florida who also appears in the documentary.
Combine rabies with the ability of a flu virus to spread quickly through the air, and you might have the makings of a zombie apocalypse.
Rabies Virus Mutation Possible?
Unlike movie zombies, which become reanimated almost immediately after infection, the first signs a human has rabies—such as anxiety, confusion, hallucinations, and paralysis—don't typically appear for ten days to a year, as the virus incubates inside the body.
Once rabies sets in, though, it's fatal within a week if left untreated.
If the genetic code of the rabies virus experienced enough changes, or mutations, its incubation time could be reduced dramatically, scientists say.
Many viruses have naturally high mutation rates and constantly change as a means of evading or bypassing the defenses of their hosts.
There are various ways viral mutations can occur, for...