Well, it's kinda like with aggressive dogs - if you show fear, they
will attack you... I know this to be fact because when we go camping, I simply ignore the mosquitoes while DW panics and ends up with big welts on exposed skin. They just never bother me 'cuz I don't let them. :W
On a serious note, we bought a natural homeopathic insect repellant that you take orally called
Mozi-Q. Haven't had an opportunity to try it out yet though. Maybe you have to believe in it for it to actually work.... It is also supposed to work with ticks, lice, black flies and even bedbugs.

We camped at Newport, Wa. last summer next to the Pend Orielle river. OMG, we have never seen so many mosquitoes and flying insects of every description as that CG. :E Nobody was outside during the daytime unless they had to be. We were booked for 7 days but packed up and left after 2 and went down near Spokane.