Areas involved with current outbreak |
Ebola Virus Disease (EBV), also known as Ebola Hemorrhagic Fever, refers to a viral infection with several different species of a filovirus. First identified in two outbreaks in the Sudan and the Democratic Republic of the Congo in 1976, Ebola causes a severe acute illness characterized by bleeding and a mortality rate up to 90%.
Most of the Ebola outbreaks to date have occurred in small villages in West and Central Africa near tropical rain forests. The natural host of the virus is believed to be fruit bats. Animals such as chimpanzees, gorillas and monkeys can become infected with the virus after coming in contact with bats; these animals are "accidental" hosts, just like humans. Humans become infected via handling blood and body fluids from infected bats or other animals. Once someone is infected with the virus they then go on to serve as a source of transmission to other humans via their own infected blood, tissues and secretions.
The incubation period for Ebola after being infected is anywhere from 2-21 days; humans are not
infectious until they develop symptomatic illness. Ebola initially is a non-specific illness characterized by sudden fever, intense weakness, muscle pains, sore throat and headache. These symptoms are followed by vomiting, diarrhea, rash, organ dysfunction and sometimes bleeding. Once symptomatic, a person's blood and body fluids are highly infectious and serve as a source for potential human to human transmission of disease.
As noted above, Ebola is associated with mortality rates of up to 90%. There is no specific treatment or vaccine for the disease.
Distribution of different Ebola outbreaks |
The WHO has terrific information on Ebola available here. Some great information is also available from the CDC.