Hello In the case of your granddaughter, if there s no sign of infection like fever, hot and swelled skin you should be relieved cause mostly it s an allergic reaction and it s not contagious. You should try to remember if she touched anything unusual before that episode starts like a plant, animal, if she played with dust or if you used a new product like soap or lotion, because it s important to know the possible allergic cause to avoid a new episode in the future. I suggest that you wait your appointment with the specialist, but if there s any new sign like fever, difficulty of breathing or any kind of symptoms you should see your doctor immediately. Hope I answered your question Wish your granddaughter a speedy recovery Best regards Dr. Noor Farid