EBOLA hemorrhagic fever is a disease caused by one of five different Ebola viruses, a virus with a high fatality rate that was first identified in Africa in 1976.
Four of the strains can cause severe illness in humans and animals. The fifth, Reston virus, has caused illness in some animals, but not in humans.
The first human outbreaks occurred in 1976, one in northern Zaire and the other, in southern Sudan. Virus is named after the Ebola River, where the virus was first recognized in 1976.
Ebola is extremely infectious but not extremely contagious. It is infectious, because an infinitesimally small amount can cause illness. Laboratory experiments on nonhuman primates suggest that even a single virus may be enough to trigger a fatal infection.
The virus is not transmitted through the air. The most contagious diseases, such as measles or influenza, virus particles are airborne.
Humans can be infected by other humans if they come in contact with body fluids from an infected person or contaminated objects from infected persons. Humans can also be exposed to the virus, for example, by butchering infected animals. The exact reservoir of Ebola viruses is still unknown
Symptoms: weakness, fever, aches, diarrhea, vomiting and stomach pain. Additional experiences include rash, red eyes, chest pain, throat soreness, difficulty breathing or swallowing and bleeding (including internal). Unprotected health care workers are susceptible to infection because of their close contact with patients during treatment.
There is no specific treatment or vaccine, and the fatality rate can be up to 90%. Patients are given supportive care, which includes providing fluids and electrolytes and food.
There have been more than 3,140 reported cases and more than 2,000 deaths since the discovery of Ebola.
Men who have recovered from the disease can still transmit the virus through their semen for up to 7 weeks after recovery from illness.
People are infectious as long as their blood and secretions contain the virus. Ebola virus was isolated from semen 61 days after onset of illness in a man who was infected in a laboratory.
The incubation period, that is, the time interval from infection with the virus to onset of symptoms, is 2 to 21 days.
Typically, symptoms appear 8-10 days after exposure to the virus