Infected

Infected is a unique ailment that is not like any of the other ailments in the game. When a unit is infected, they will die and turn into a regular Zombie within 1-3 minutes. There is no visual way to identify an infected unit from others other than the debuff icon.

Hades (Second Form)
Hades' Tentacles have a 10% chance to cause Infection on biological units it attacks.

Medic's Anti-Venom
An innate skill that every Medic will have, the Anti-Venom skill does have peculiar hotkey attached to it. It is found under Marine Actions, so the full hotkey is X then V. Many new players will not know this, and take a long time to figure out on their own. Either way, this skill has a short cooldown, low energy cost, and can be used many times if the Medic has a healthy supply of energy.

Chemical Expert's VRL-772
Has a higher energy cost and longer cooldown than the Medic's Anti-Venom but still works nonetheless. Also has the added benefit of curing other ailments and giving an attack and movement speed bonus as well.