Irwell wrote:

There is an annotated version of Bram Stoker's "Dracula",
probably explains it in there. I read it whilst in hospital,
one of the nurses thought it was an odd choice of a book
to read in a hospital.

Oh, I dunno .... seems totally appropriate to me! (The medical
profession being "bloodsuckers" in more ways than one, at least here in
the U.S.) (;-)