 Folkloric vampirism has been associated with clusters of deaths from unidentifiable or mysterious illnesses , usually within the same family or the same small community . The epidemic allusion is obvious in the classical cases of Petar Blagojevich and Arnold Paole , and even more so in the case of Mercy Brown and in the vampire beliefs of New England generally , where a specific disease , tuberculosis , was associated with outbreaks of vampirism . As with the pneumonic form of bubonic plague , it was associated with breakdown of lung tissue which would cause blood to appear at the lips . 
