Zombies!!

Mathematical models demonstrate that most movie concepts of Zombie outbreaks are close to correct or even understated. Zombies and other Zombie-like things must be destroyed with utmost haste to limit the spread of infection if society is to survive.

In summary, a zombie outbreak is likely to lead to the collapse of civilization, unless it is dealt with quickly. While aggressive quarantine may contain the epidemic, or a cure may lead to coexistence of humans and zombies, the most effective way to contain the rise of the undead is to hit hard and hit often. As seen in the movies, it is imperative that zombies are dealt with quickly, or else we are all in a great deal of trouble.

And then the humor:

Clearly, this is an unlikely scenario if taken literally, but possible real-life applications may include allegiance to political parties,...

Oh, yes. Brain-eating, society-destroying political parties that rapidly infect hordes of followers must be dealt with quickly and completely.

And remember that you must shoot for the head.