My son got this a little before his first birthday...started as 3 bumps, which the doctors told us at several different visits to wait, it will go away. It got MUCH worse, and we finally couldn't take it and took him in to an excellent dermatologist. After a couple months of treatment, it is finally (knock on wood!) gone. I am so happy - and I wish we would've gone in when there were only 3 spots. That would've been much simpler.... Please take him in. (Also, keep his skin moisturized, when you're dry and itchy, you scratch and can spread it more easily.)
Note: I did try that SilverCure after talking to my pediatrician (6 mos after diagnosis). My son was too young for this to work well on. He didn't understand and couldn't sit still and not touch long enough for it to dry and really hated the whole process/fought us with it. I heard mixed reviews from people on using that, but we were willing to try about anything. I really wished I would've gone to the dermatologist earlier...all in all, it took a total of a year before they were gone - 6 months of waiting hearing the dr say they'd go away on their own, then a month or two with the SilverCure, then finally the dermatologist. I can't imagine how much longer they would've been around for if we hadn't taken him in to the dermatologist. :(