It looks like the fan-favorite mode will likely be coming to the Halo:Master Chief Collection soon too. In a Halo Waypoint post, 343 let on that the mode would be added soon saying:
The playlist team continues to work on future updates, and it's quite likely that we'll be talking more about things like Infection in the coming weeks.
This will be welcome news in my circle of regular Halo players. There is nothing quite like riding away on a mongoose from super fast zombies on Sandtrap. That's what I'd like to see at 60fps.