Ebola virus disease (EVD), Ebola hemorrhagic fever (EHF), or simply Ebola is a disease of humans and other primates caused by an ebolavirus. Symptoms start two days to three weeks after contracting the virus, with a fever, sore throat, muscle pain, and headaches. Typically, vomiting, diarrhea, and rash follow, along with decreased function of the liver and kidneys. Around this time, affected people may begin to bleed both within the body and externally.
The virus may be acquired upon contact with blood or bodily fluids of an infected human or other animal. Spreading through the air has not been documented in the natural environment. Fruit bats are believed to be a carrier and may spread the virus without being affected. Once human infection occurs, the disease may spread between people, as well. Male survivors may be able to transmit the disease via semen for nearly two months. To make the diagnosis, typically other diseases with similar symptoms such as malaria, cholera and other viral hemorrhagic fevers are first excluded. To confirm the diagnosis, blood samples are tested for viral antibodies, viral RNA, or the virus itself.
Prevention includes decreasing the spread of disease from infected animals to humans. This may be done by checking such animals for infection and killing and properly disposing of the bodies if the disease is discovered. Properly cooking meat and wearing protective clothing when handling meat may also be helpful, as are wearing protective clothing and washing hands when around a person with the disease. Samples of bodily fluids and tissues from people with the disease should be handled with special caution.
No specific treatment for the disease is yet available. Efforts to help those who are infected are supportive and include giving either oral rehydration therapy (slightly sweet and salty water to drink) or intravenous fluids. The disease has a high risk of death, killing between 50% and 90% of those infected with the virus. EVD was first identified in Sudan (now South Sudan) and Zaire (now the Democratic Republic of the Congo). The disease typically occurs in outbreaks in tropical regions of sub-Saharan Africa. From 1976 (when it was first identified) through 2013, the World Health Organization reported a total of 1,716 cases. The largest outbreak to date is the ongoing 2014 West African Ebola outbreak, which is affecting Guinea, Sierra Leone, Liberia, and Nigeria. As of 28 September 2014, 7,157 suspected cases resulting in the deaths of 3,330 have been reported. Efforts are under way to develop a vaccine; however, none yet exists.