This is the appearance of the rash of Rocky Mountain Spotted Fever on the hands and forearms. The rash starts on the hands and feet and later spreads to the trunk. It is caused by a bacteria transmitted to humans by a tick bite. (Image courtesy of the Centers for Disease Control and Prevention.)
Update Date 5/1/2015
Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.