http://news.bbc.co.uk/2/hi/science/nature/8206280.stm

They were modeling a highly infectious disease, so they figured why not use a zombie plague? Excerpt:

To give the living a fighting chance, the researchers chose "classic" slow-moving zombies as our opponents rather than the nimble, intelligent creatures portrayed in some recent films.

"While we are trying to be as broad as possible in modelling zombies - especially as there are many variables - we have decided not to consider these individuals," the researchers said.

...

Even so, their analysis revealed that a strategy of capturing or curing the zombies would only put off the inevitable.

In their scientific paper, the authors conclude that humanity's only hope is to "hit them [the undead] hard and hit them often".

They added: "It's imperative that zombies are dealt with quickly or else... we are all in a great deal of trouble."
Nice to see people with a sense of humor.