Ebola is a rare and serious infectious disease that occurs in Africa and is accompanied by bleeding in the body. The official name of the disease is Ebola haemorrhagic fever, caused by a virus (the filovirus). Other filoviruses that may cause haemorrhagic fever are the Marburg virus and the Lassa virus.
The disease can be contracted only through direct physical contact with a patient or as a result of slaughtering and eating a sick animal. If contaminated, there is a considerable risk of dying; in Africa, over half of sufferers die. It is unknown whether this is also influenced by poorer medical facilities. There is no vaccine or proper treatment against Ebola, and treatment mainly consists of fighting complications. The Ebola disease was named after the Ebola river in Congo, where the first case of the disease was presented in 1976. In that year, outbreaks occurred in Sudan and former Zaire (currently the Democratic Republic of the Congo). In the years after that, Ebola caused several epidemics in African countries. Early 2014, an outbreak was reported in West Africa, in the Guinea rain forest area on the border with Sierra Leone and Liberia.
Contamination and symptoms
Bats are the most probable source for filoviruses. Viruses have been found in various bat species that are native to Africa and which can also spread the virus through their defecation. Various animal species living in the African tropical rain forest can be contaminated with the virus, such as chimpanzees, gorillas and antelopes. The slaughtering and consumption of these animals can also lead to becoming infected by the virus.
After becoming ill, humans can contaminate other humans through direct contact with blood, defecation, urine, sperm, vomit and sweat. The spreading of the virus through the air (by sneezing or coughing, for instance), has never been demonstrated. On average, the time between being infected by the Ebola virus and becoming sick is a week. A patient is infectious if he/she suffers from symptoms such as fever, headaches and muscle aches, in addition to other symptoms that may occur. The most characteristic aspect of the disease is that the virus may cause inflammation in small blood vessels, possibly resulting in patients suffering from haemorrhaging in various parts of the body. This is the time when the patient is most contagious.
Spread and frequency
Ebola is an extremely rare disease with occasional local outbreaks in Africa. People can only be contaminated after direct contact with other people or with animals infected with the Ebola virus.
Control and prevention
An outbreak of Ebola is controlled by quickly recognising and separating (isolating) patients to prevent new contagions. People who have been in direct contact with a patient are followed/monitored for a period of time to see whether they become ill. If so, they are immediately admitted to hospital, where they are nursed separately from other patients. Contamination can be determined through a blood test in the laboratory.