Epidemics and the end of humankind | Rosalind Eggo | TEDxThessaloniki

Which is good news for our species, of course, as long as the survivors, the people left, like each other enough to repopulate the planet. (Laughter) That's good news. But generally what I do in my job is not try to just let pandemics happen. The goal of my work is to try to understand the mode of transmission well enough to develop and evaluate preventive measures. Preventative measures are measures such as closing schools, urging people not to go to work when they are sick, and vaccinating people. The goal of these precautions is to reduce the reproduction rate (the rate of the number of secondary cases) to less than one.

This is because if each infected person infects less than one person, the epidemic will decrease. This, then, is the objective of my work. Now I have to tell you about an exception. Because there is always a “but”. There is a monoinfection that can be a problem. It's something people like to think about so much that they've even made some movies about it. It's a zombie infection. (laughs) So while it's a little funny, it's important to look at the zombie infection and figure out why it's an infection that can wipe out every person on Earth. So what we're going to do is take the same model that we used before.

We have both the susceptible group, the infected, the recovered and the transmission rates. The transfer rate is divided into four sections. So why can a zombie infection wipe them all out? Well, first of all, zombies break this first rule. In our model, we assume that people can recover from an infection. As I understand it, no one recovers from a zombie infection. There are no movies about people who felt bad over the weekend and went to work on Monday. (laughs) The other thing we assume is that if people die from an infection, they stay dead, unlike zombies. (Laughs) This breaks that model rule.

The other thing is that the possibility of infection from coming into contact with a zombie is very high. I think it's 100%. For an infection like the flu, if you see someone infected, it's 10%, but with zombies, you'll never see someone with just a scratch on their skin and you won't get the infection. Then break that rule. Finally, remember how I told you that we assume that people come into contact with others randomly? Well, zombies go out looking for impressionable people. This breaks that rule. This means that the only pandemic that can truly infect everyone and wipe out humanity is a zombie apocalypse.

This is actually good news because zombies are not real. Thank you so much. (applause)