Filoviruses (Ebola and Marburg) are highly contagious pathogens, which cause severe and often fatal illness in humans. Health workers are at increased risk of infection because of their close and prolonged contact with severely ill patients with a high viral load. The risk of transmission of Ebola virus can be reduced if appropriate measures are taken, including the use of personal protective equipment (PPE).
http://apps.who.int/iris/bitstream/10665/251426/1/9789241549721-eng.pdf?ua=1