On her second night in San Myshuno, my sleeping sim was attacked by a vampire. The front door was locked (which shouldn't bar the vampire) and my sim awoke dazed with the vampire in the apartment hal...
OK, my sim has had five attacks in eight sim days. LaBst night it was Lilith Vatore and I did get to freeze her too, @BlkBarbiegal. So far none of the vampires have been able drink from my sim. I may have to put the garlic up to stop the attacks.