Continuity mistake: When Andy gets sprayed with blood at the virus outbreak scene, when a sniper saves his life the blood splatter changes several times over the movie. (00:54:15)
Continuity mistake: Don attacks a man in the underground carpark and thumbs out his eyes as he did with his wife. The man gets up in the next shot perfectly OK.
Continuity mistake: When the plane lands at the airport, it is a Boeing 737 without winglets. When it taxis to the apron in the next shot, it is a Boeing 757. Then again it is a 737 with winglets, then without and finally with them.
Continuity mistake: After Don escapes from the house at the beginning of the film, the infected are right behind him. He manages to escape in the boat but when the following shots show the river, there is no sign of any bodies or blood (despite one infected being killed by the boats propeller) or any disturbances on the surface apart from waves being caused by the boat. There is no chance that the infected could have all gotten out of the river so quick (including the dead infected body) without leaving so much as a splash. (00:10:35)
Answer: I suspect that it's really not that simple. Remember that in the first film, Jim was lying alone in a hospital bed for some considerable time before waking to the deserted London. He would certainly not have smelt clean and fresh, yet he was still clearly detectable as prey by the infected. While being nice and clean makes it easy for them, it seems clear that it's not the sole indicator that triggers an attack.
Tailkinker ★