I used to have the same thing on my back. That was a couple years ago when I was a teenager, though. Mine just kind of went away, but I'll tell you what helped me. I'd scrub them gently with a luffa and soap each time I showered, try to keep the area clean and moisturized, and never picked at them. When you pick at them, they get worse and/or spread (that's what my dermatologist told me).
Mine started to go away after a little more than a month doing that. They'd come back if I stopped, so I kept doing it and it worked. If you're having problems with it, you might want to talk to a dermatologist.