My mum was bitten by a staffy in her late 20s. She had a decent bite, but I think the random unprovoked nature of the attack scared her more then anything.

She was ok with the 70kg Shepard with the nickname "bear", but couldn't bring herself to to relax around the 10kg staffy even after all that time had passed. Think it was the first one she'd allowed herself to be in close proximity with since then