Trivia

Leticia Dolera had previously portrayed Angela Vidal, the reporter of the previous REC films, in the parody Spanish Movie (2009). The "REC" scenes also featured directors Jaume Balagueró and Paco Plaza.

Comic book artist Tony Moore, known for his work in The Walking Dead (2010) comic book series, drew a poster for this film's promotion in the United States.

The origins of the demonic outbreak are explained in the graphic novel "[REC]: Historias Ineditas" (Untold Stories), released alongside "Génesis" in Europe.

In an apparent creative departure, the possessed/infected behave and appear slightly different than in the other installments. In this movie, they are depicted as slower and more easily defeatable, in the molds of George A. Romero's classics.

Actress Leticia Dolera and Manuela Velasco, star of the first two REC films, share the same birthday, though Dolera is six years younger.