Ottaviano Dell'Acqua's hair and beard are visibly longer in the scenes shot after Lucio Fulci left, such as when he is fighting the bald zombie at the abandoned kiosk, and his final scene with the anti-contamination squad.
15 minutes into the film, a room service boy enters the infected mans bedroom to bring him water. After he leaves, he asks a female colleague to clean the room. When she enters, it is clearly a completely different room.
In the opening credits scene, when the helicopter is approaching the compound and is landing, the interior shots show it almost having landed, while the inter cut exterior shot have it much higher up in the air.
When Commander Bryant is explaining to Professor Holder that not even the military were aware of the potency of Death One (after Holder's line, "You should have told us about the risks involved!") the shadow of a camera is visible on the wall behind the General.