Maybe my mosquitos are different than yours (just looked, and there are 3600 different kinds). Usually when I take my dog out so she can “commune with nature”, I’ll end up getting bit two or three times by mosquitos. I never feel them at all, except for the itchy bumps after the fact. Could be me. I only ever get bit on my legs/ankles.
As for bite time, I don’t think it’s the length of time the mosquito feeds, but the act of breaking skin and feeding. The malaria parasite will cause the mosquito to bite over and over again, which probably increases the infection rate.