Cell infected with herpes virus. Coloured scanning electron micrograph (SEM) of herpes simplex virus-1 (HSV-1) particles (pink) being released from a host cell. This virus infects epithelial cells around the mouth, causing fluid-filled blisters known as cold sores. There is no known cure for herpes infection and the virus remains in the body for life. Magnification: x3,450 when printed at 10 centimetres wide.
Credit: SCIENCE PHOTO LIBRARY