Many people who are interested in the spread of infectious diseases have co-opted the zombie craze in order to emphasize key preparedness messages that are "common" to both, including the CDC (I even have a CDC zombie hunter shirt).
One of the best known popular culture items in this social phenomena is the novel and movie World War Z which depicts an outbreak of an unknown infection that turns individuals into rabid zombies. There are many epidemiological points made in the movie but the one that I want to focus on regards who is susceptible to infection and who is immune.
This is a major question in any outbreak and, just as in World War Z, figuring out the reason why is often a game-changing discovery. For example, in HIV there is a well known mutation that a portion of the populate harbors in CCR5, HIV's co-receptor, that can render one unable to be infected (see The Berlin patient). In a similar fashion, sickle cell trait confers resistance to malaria.
In the case of HIV, understanding the role of the CCR5 co-receptor led not only to The Berlin Patient's path-breaking bone marrow transplant, but to the development of the drug mariviroc. Mariviroc blocks CCR5 thwarting the ability to the virus to infect cells and is a component of modern HIV drug cocktails.
So, in the early days of an outbreak understanding who is being spared is as important as understanding who is being infected--a little bit of zombie pedagogy.