Plague of the Manitou — Graham Masterton

Virus expert Anna Grey is disturbed when a dying patient is wheeled past her lab vomiting fountains of blood and screaming like a banshee. To make matters worse, when she examines the man's corpse, she could swear she hears him whisper: ‘Get it out of me.' John Patrick Bridges is dead. He's definitely dead. But if he's dead -- how is he talking?

Anna wonders if she's going mad. But then a second man hemorrhages and dies; yet Anna hears him whisper, ‘Please help me.'

There is no such thing as demons, Anna tells herself. But cynical fortune-teller Harry Erskine knows otherwise and a series of extremely disturbing events are forcing him from his Miami home towards the bereaved Anna, who as yet has little idea of the evil she is facing...