"Parasite Eve" originated in 2019 when frontman Oli Sykes read an article about a Japanese superbug that had become heat resistant because of climate change. Borrowing the title from a late 1990s action role-playing video game, he came up with the idea for a horror song about a deadly virus. Bring Me The Horizon started to record the track in February 2020 before COVID-19 really took hold across the globe.
As the pandemic started to sweep worldwide, the band felt the parallels were too similar so set the song aside. "It was really weird," Sykes admitted to NME
. "We'd heard about the pandemic in China, but then the similarities between what we were writing about started to become closer to reality. Every time there was a news story about it, we'd turn to each other and say 'Parasite Eve', not realizing the magnitude of it all. We shelved the song for a bit because it felt bit too close to the bone."
Lockdown triggered a writing process that began to align and merge the boundaries between isolation and the virus. As time went on, Sykes and keyboardist Jordan Fish concluded the song applied to the times and that instead of shying from it, they should embrace the dark side. Through a series of video calls and remote recording, they completed "Parasite Eve" and released it as a single on June 26, 2020.
"In our music we've always wanted to escape, but there's been too much escapism and ignoring the problems in the world. It's not what the world needs," Sykes explained to NME
. "The world needs more and needs to think about it and remember. You can't just brush over it and expect life to go back to normal, because it f--king ain't. In so many ways, we need to change. That's what rock music is about - addressing the dark side and processing it."