Ebola is a severe, often fatal, disease. It is caused by a family of viruses called orthoebolaviruses. There are four types of viruses that have caused Ebola virus disease in humans: Ebola (Zaire), Sudan, Bundibugyo, and Tai Forest. All cause similar symptoms and are spread in the same way, though the prevention and treatments available vary by the type of virus.
Ebola viruses infect humans through contact with animals that carry the virus (through hunting, handling, or eating infected animals). Person-to-person transmission occurs through direct contact with:
People become contagious after they begin to have symptoms, such as fever.
Ebola does not spread through the air. There is no evidence that Ebola is spread by coughing or sneezing. Ebola is generally not spread during brief, casual contact, like a handshake or bumping into someone.
The disease usually starts with a sudden fever, along with headache and joint and muscle aches. Other symptoms may include:
Symptoms may appear from two to 21 days after exposure but usually appear within eight to 10 days. The severity of the disease can vary based on the type of Ebola virus. Average death rate of Ebola disease is about 50%, though this can vary between 25% to 90%.
There are currently two medications approved by the U.S. Food and Drug Administration for Ebola caused by the Zaire virus. There are no approved medications for other types of Ebola, including Bundibugyo virus, though there are vaccines and other medications that are under development.
Treatment focuses on supportive care and may require intensive care unit support.
Generally, people in the United States and travelers have a very low risk of getting infected with Ebola. If you are traveling to areas where there is an Ebola virus disease outbreak: