What is the message behind Dracula?What is the interpretation of Dracula? What does Stoker trying to teach the reader by Dracula?
There are a number of interpretations we might make if we read the story thematically or symbolically.
I'd like to say that the Dracula story functions as a counter-part to our notions of idealized eternal life. What if we were granted our wish to live a human life forever, but we must become a monster in the process?
Taking this as the comment, we can see the story as an expression of the idea that human life is only "human" within its natural limits.
The most obvious less to me is the nature of good and evil. A person can try to be good, but be “infected” by evil, just as metaphorically a person becomes infected as a vampire. Then you live a cursed life, rather than a life of eternal bliss.