While being attacked by Players/AI - you can simply hold a defensive/blocking stance to prevent damage to a player (unless it's cancelled by receiving a heavy attack - which can *only be inflicted by players, not infected ai). To prevent players from abusing the block feature against infected, introducing a mechanic to allow for stamina depletion while blocking may be a promising solution/method to mitigate this issue.

When a player's stamina runs out, they will be unable to maintain a defensive/blocking stance (and could additionally be given a unique exhausted block stance/animation) until their stamina has regenerated past a certain point. This feature could then be configurable via the cfggameplay.json file to modify the depletion of stamina while in a defensive/blocking stance.

The addition of trivial features like this would expand on the "bloodthirsty" infected AI and present players with a genuine threat when engaging with them.