How long would it take for zombies to take over the earth during a zombie apocalypse? | | i love WEREWOLVES

If you think you can survive the zombie apocalypse, you might want to think again! A scientific study conducted at the University of Leicester and published in their Journal of Physics Special Topics predicts the outcome for a zombie outbreak is not good. Humans would not last very long at all. In fact, the prediction is that given a world population of 7.5 BILLION people, there would only be 273 humans left after 100 days! Yes, that's right, if a zombie outbreak happened, only 100 days later, practically the whole planet would be wiped out and zombies would take over the earth! The study, which was conducted by university students, used the SIR model which is a scientific model used to calculate the infection rate of a contagious disease. In the study, there are two basic things which are assumed about the zombies. First and foremost, it is assumed that the zombies can live 20 days without food. Second, it is assumed that there is a 90% chance that each zombie will infect one