Prevention: Stay inside at dawn and dusk, and avoid playing near standing water like ponds and puddles, where mosquitoes like to congregate. Repellents containing DEET are effective, but the American Academy of Pediatrics recommends using ones that contain no more than 30 percent DEET on children. Never apply on babies younger than 2 months.
Treatment: Tell your child not to scratch -- he'll break the skin, which can lead to infection. To minimize itch, apply an over-the-counter hydrocortisone cream (1 percent), a baking-soda-and-water paste, calamine lotion, or diluted tea tree oil. Oral antihistamines like Benadryl provide stronger relief, but check with your pediatrician first.