Is Staphylococcus aureus the only bacterium that causes impetigo?

Older textbooks state that the most common cause of impetigo (impetigo contagiosum) is group A β-hemolytic Streptococcus. In recent years, most infections in the United States have been due to S. aureus, but the prevalence varies geographically. Although impetigo may be due to either organism, in many cases, both can be cultured. In these cases, it is thought that the streptococci are the primary infection and the staphylococci are secondary invaders after the infection has damaged the skin.