The Frostbitten Worker is one of the different variants of Zombies. It only appears in the new snow biome. When the apocalypse began little is known about what happened to most of the survivors who lived in the snow biome. Still, it looks like this poor woman didn't make it out. They appear to be slightly larger than most female zombies, however, she is just as fast in the dark as they are.
The Frostbitten Worker, Frozen Lumberjack and Frigid Hunter all seem to share similar traits when it comes to health. As of Alpha 6, all snow zombies appeared to have the same amount of health as a Bloated Walker, requiring 2 pistol headshots to bring them down.
This zombie has the easiest head movement patterns of all three snow zombies; long-range Crossbow headshots are the easiest against this zombie. Still, it hits as hard as all other three.
During the night, this zombie becomes extra-dangerous, since it hits as hard as a Bloated Walker with as much running speed as the standard zombie.