My wife NEVER gets a mosquito bite. She doesn't use anything to ward them off either. They flat will not land on her. I've sat right next to her, me with several buzzing, landing and biting me and her, they buzz her but won't land. I have no idea why but if it can be figured out, there's a fortune to be made.
She also does not get poison oak reaction either. She can pull the plant out by bare hand, wipe her forehead, etc and not get poison oak. I can get it petting the dog if it's walked through the stuff.
We took our grand kids camping a couple nights ago with instructions we were to not use DEET on them from their parents. We tried those candles, coil wrist bands, citronella spray, etc, but they got chewed on good. My 4 year old grandson has over a dozen bites on his face after only 2 hours exposure. (We left first light next day).
I used DEET and got bit through my clothes as I used the towelettes and wiped it on my exposed flesh only.
We used some sort of OFF thing that hangs around your neck with a fan in it and a wafer of repellent, but it did nothing. I have had success with that thing hanging in a camper to keep the skeeters from going inside as the door opens and closes. Just not while carrying it and walking around outside.