Marburg hemorrhagic fever is a rare, severe type of hemorrhagic fever which affects both humans and non-human primates. Caused by a genetically unique zoonotic (that is, animal-borne) RNA virus of the filovirus family, its recognition led to the creation of this virus family. The four species of Ebola virus are the only other known members of the filovirus family. In cases of Ebola, symptoms typically begin to develop within about four to six days of being infected. Symptoms of Ebola commonly include such things as fever, sore throat, vomiting, weakness, stomach pain, and a dry, hacking cough. Death usually occurs during the second week of Ebola symptoms, most often as a result of massive blood loss.