We cannot ignore the promiment importance of the bite and just what it signifies. All of our faveroite monsters have one key thing in common. The Vampire, the Werewolf, and the Zombie, they pass on thier curse if you will through a bite, and not just a bite, but it always involves some exchange of fluids to some degree.
There are two ways in which to understand and view this, for one, the fact that it is like the spreading of a disease, as well most these conditions, have some link to blood. The Vampire obviously feeds upon blood, and Zombies are seen as having a virus in the blood stream, and the lycan feed upon the flesh of thier victims, and can seen has exhibiting some blood drinking behavior in this, as well the brutal way in which they are often thought to kill, which tends to lead to the loss of vast amounts of blood.
But you can go beyond just the concept of a diseas, and venture further to the idea of an STD, and the clear sexual symbology. though this does hold most true for the vampire above all else becasue of his clear sexual nature, but to some degree it can be glimpsed in the others. As all involve a pentration of the skin, and drawing fluids out, and in the case of vampires and zombies this often also involves the exchanging of fluids. As it is comonly beleived to become a vampire, not only most one be bit, but they also must drink of the vampires blood as I have discussed, and with the zombie, it is not just the bite itself that changes one, but having dna of the zombie entered into the victims system which is very much like an STD though one can agree that zombies are not in nature sexulaized.
Yet on the other hand, though the disease anagloy works with today, and our world of science and understanding blood borne passegens, these myths have been around long before that, which is what makes it so difficult to escape the sex factor, afterall, that is one of the things that was held in great fear the idea of one giving into thier passions, of becoming animal like a discussed before each of the 7 sins are aspects of our animal nature that needed to be control and of course one of the biggist was Lust.
I know I have discussed this more then once, but that is becuase of the simple fact it is something that just simply cannot be escaped in discussing these topics.
The fear of the vampire, the werewolf, and even the zombie to some degree boils down to the fear of man uncontroled, man treturning to his nature that he tries so desperately to repress.