[InfernoImmortal]

Hello, I'm a newbie scripter and I am currently working on a zombie script.
Everything is going fine excpet one part a "/bite" commands, althought I have seen on some servers, zombies bite while the player presses the "alt" button, would be cool if someone could give me a couple of hints how it works and/or script it for me.
So what I basically need is:
A bite script which works for one class only (zombies)
When someone gets bitten a message should appear for all players that are close (like 10-15 IG meters)
"Radom_Zombie1 grabbed Random_Civilian1 and bit him".
The bite does 15 points health damage to the target, ignoring armor and restores 15 points of health to the zombie.
After that the target gets infected and loses 5 health points every 15 seconds, and if the target dies while infected he becomes a zombie, pretty simple huh? Oh and the bite cooldown should be 10 seconds

(Don't forget to explain how it works, I'd like to know more about scripting so I can finish the server one day)

EDIT: The bite radius should be really small.