the spreader will well. spread the infection his main attack is just a small swing of his arm pressing [E] will make him do a bite animation, players that are hit with this move are "infected" after a while that player will fall over, and by random chance they MIGHT get a mutation (becoming a stronger special infected, any zombie other then the basic one) they will still wear what ever they have just diffrently (I.E the tank will have no sirt but pants will stay the same, for the stalker there sirt and pants will we E X T E D E D) but if the infected has an item (I.E the tanks club) the "infected" will be different (the tank will pull rock out of the ground for throwing and swing his fist as a melee) killing one of these "infected humans" they will drop what a normal human would drop when killed (I.E medkits and other items) the spreader dosent spawn that often but has a high chace of spawing at the start of a round.
also when i use the word "infected" im most likly using it for the player infected by the spreader
sorry for bad spelling