Macacine herpesvirus 1, also known as B virus, is an alpha-herpesvirus that naturally infects Asiatic macaques. It is transmitted by exposure to contaminated bodily fluids. In macaques, the infection is similar to that of HSV-1 and HSV-2 in humans and serious disease is rare. However, in humans, it invades the central nervous system and causes serious encephalitis with a fatality rate greater than 70%.
