Croup

My 7 month old had a fever for a week and then developed a cough. We took him to the ER due to his breathing and he was diagnosed with croup. He recieved a nebulizer and steroids. A few days later we followed up with his pediatrician and he was prescribed another round of steroids. All in all he's now been home and away from other people and kids for 15 days. He still has a cough no fever. Is he still contagious? I am worried about getting anyone else sick before Christmas. We were told he was contagious for 7-10 days.