The advent of zombie-themed movies and TV series has prompted questions about what could happen if a zombie apocalypse indeed happens in the real world.
Now, another team of researchers has conducted a study that offers insight on how fast a zombie infection could devastate and possibly wipe out humanity.
Students from the University of Leicester in the U.K did math to investigate the spread of the zombie virus using a basic epidemiological model, the SIR model that describes how an infectious disease spreads through a population.
Between 100 To 200 Survivors By Day 100
The researchers worked on the assumption that each zombie could only find one victim per day and has 90 percent chance of infecting this person with a zombie virus making the virus about twice as contagious as the pathogen responsible for the black death. The zombies are also assumed to have an undead lifespan of 20 days.
With these parameters applied into the epidemiological model, the researchers found that within a period of only 100 days, the human race would only have a few hundred survivors left from a zombie apocalypse.
Using the SIR model and with only one person infected at day zero, the researchers found that the surviving number of people by the 100th day of infection would only be between 100 and 200.
The researchers, however, noted that they did not account for other factors that can possibly influence the number of people who would survive. For one, birth and death rates were not factored in. The researchers did not also include the possibility that humans can kill zombies which can give mankind a better chance of surviving a zombie apocalypse.
The assumption of one zombie turning only one person into a zombie per day also becomes less realistic when the zombie to human ratio increases.
"Natural birth and death rates have been neglected since the epidemic takes place over 100 days, so the natural births and deaths are negligible compared to the impact of the zombie virus over the short time frame," the researchers wrote in their study. "We have also not included the possibility for the humans to kill the zombies. Including this may give the humans a better chance at survival."
Hope For Humanity
In a second study, the researchers accounted for the survivors being able to kill the zombies as well as the reproduction rate of the population. The findings show that if humans fight zombies, the future of mankind is not as bleak as the one suggested by the first study.
"We investigate the SIR model applied to a zombie epidemic and introduce new parameters such as the rate at which zombies are killed," the researchers wrote. "We find that it is actually possible for our population to survive the zombie epidemic under these conditions."
The findings of the two studies were published in the student-run journal of University of Leicester, The Journal of Physics Special Topics, on Nov. 22.