Breaking ranks with an established mythos
Everyone knows how lycanthropy is spread – the full moon turns the werewolf mad, and in his ravening hunger he gallops, uncontrolled and terrifying, in search of any available human prey. When he finds someone, he will rip and tear until the person is dead. Unless something interrupts. Any surviving victim is doomed in turn to repeat the cycle. Reviled. Out of control. Monstrous.
What if there were other ways to spread the infection? Say, through the local Bloodmobile? The dear sweet little old lady volunteers who handed a can of juice and a cookie to the donor and thanked him for taking time out of his day, would never know what he had done.
What would happen to the recipient?