You don't have to sit back and just passively put up with insects, especially those that like to bite (mosquitoes, wasps etc.). Eat asparagus and your sweat will develop an odor that repels insects. Or apply lemon oil to your skin. If you are bitten, there are natural substances to soothe the irritation. Aloe vera has extraordinary powers of soothing skin disorders. It is available in forms for both internal and external application in most health and beauty stores.
If you have one of these amazing plants growing at home, cut the tip off one of the leaves (the leaf will heal itself). Apply the pulp and juice to the itching or swollen area. Lightly boiled cabbage or leek makes an excellent analgesic poultice. Of course, if you are hiking in the woods, you might have a little trouble finding cabbage! Plantain also works well. Cut it and rub it to get to the juice then apply it to the affected area.