Kills the Survivor with the lowest influence value.[/quote]
Wouldn't a bite kill the character for whom the exposure dice was rolled, regardless of their level of influence? You'd only roll the exposure dice normally when moving or attacking a zombie with a specific character, e.g. if Maria Lopez and Forest Plum are both in the same location, if I attack a zombie with Maria Lopez and roll the bite symbol, Maria dies, not Forest (although he would then be the next to roll as the infection spreads).
You are correct. The question raised in the subject header is about the spreading, after the bite victim dies.
And it is correct that Helpless Survivors do not die from spreading the bite.