How To Treat Small Red Pimples In Children?

My 6 yr old grandson has some small pimples on his body and has had them for a couple of years - very small and never bothered him. The doctor says its a virus and that they will disappear in time. We have been about 4 times over the last couple of years and he says the same everytime. One of these spots has become infected, he could have scratched it. Whats the best thing to do till we can get him to see the doctor. It is red and angry-looking.