Or, thats what I believe. Maybe not the way that most of you might think. I dno't believe in your traditional movie zombie apocalypse. No, that is unlikely..
I did a bit of searching. I found this article. Take it for what it is, s it may just be mumbo-jumbo, but it doesn't seem too far fetched to me.
Now, to highlight the main points, we have brain parasites, Nerotoxins, Rabies, mad cow disease, etc (that could end up adapting and mutating in which case being highly likely for zombie symptoms, reanimation research, Nanobots, and Helacyton gartleri cancer cells which do not die. If you read the article, it will explain in a little more detail what each of these are and how they can effect us and relate to zombies.
Have a read through, and discuss.