Why don the infected zombies in 28 days later attack each other?
It has been explained in the graphic novel, 28 Days Later: The Aftermath, that the infected target their victims through smell. Uninfected individuals smell of perfume, deodorants, soap, etc., while those that are infected would reek of perspiration and dirt. One could also conclude that the virus would be counter-productive if an infected individual attacked another infected individual. One could conclude even further that the action is all done in tradition of the earlier zombie films that influenced it.
