Like lots of other ideas that come from myths and legends, it is really difficult to define what exactly it means to be a “vampire”, as all the books and films have a slightly different idea of what that means!
But the general idea of humans feeding off other humans blood, etc, etc, I don’t think is very likely.
There are vampire bats that have a two pronged bite and feed on animal (and human) blood. They also only feed at night. Part of the vampire stories are probably based on them.