Infection problem

I also know the glitch. But very few people know how to use it. Like me.

 

If you're talking about zombies having bows and armour, then a bow is a prestige 7 zombie perk, and you can get human armour for a zombie with a donator kit

 

It is a glitch. Not sure about the armour, could be from a kit, but there's no way to get a bow as zombie unless you're p7.