Ex Virus doesn’t kill

“The doctor nodded. “That’s what’s why it’s taken so long to isolate this. During the outbreaks, everyone was operating under the misconception the virus was lethal and somehow reanimated people. But it isn’t. It’s two separate things.”
“Wait,” said Gorgon. “How isn’t it fatal? Everyone who gets bitten dies within two or three days.”
“Yes, they do,” she nodded. “Here’s where it gets interesting. You’ve all heard of the Komodo dragon, yes?”
Most of the heads in the room nodded.
“Okay, for years people thought Komodos were poisonous because their bite was so lethal. Turns out their saliva is like the agar in a petri dish. It’s a perfect growth medium, so it’s just brimming with every bacteria and virus present in the tropics. They bite you, break the skin, and all that stuff gets shot straight into your bloodstream. Suddenly your body’s dealing with thirty or forty major infections at once.”
Stealth steepled her fingers. “And this is what exes do?”
Connolly nodded. “When a person dies, lividity sets in, and all the fluids in their body start heading down. Since they’re still standing, exes have a lot of material build up in their jaws and cheeks. The brain gets heavy blood flow, so anything in the bloodstream ends up there.”

Excerpt From Ex-Heroes, pg 184-185
Peter Clines
https://books.apple.com/us/book/ex-heroes/id585738407