Ebola and Marburg haemorrhagic fevers are caused by the Ebola and Marburg virus respectively, both belonging to the same virus family. Both are rare diseases, but have the potential to cause high death rates. There are five species of the genus Ebolavirus (Filoviridae family): Zaïre ebolavirus, Sudan ebolavirus, Reston ebolavirus, Taï Forest ebolavirus and Bundibugyo ebolavirus.
Ebola virus disease is not an airborne disease and only symptomatic patients are contagious. Transmission requires direct contact with blood, secretions, organs or other bodily fluids of dead or living infected persons or animals. Therefore the risk of infection is considered very low if precautions are strictly followed.
Clinical illness starts as a flu-like syndrome, rapidly evolving to severe disease with bleedings. No treatment or vaccine is available for either disease.
An outbreak of Ebola virus disease with onset in December 2013 and recognition in March 2014 is still ongoing in Guinea, Liberia and Sierra Leone. On 8 August 2014, the World Health Organization (WHO) declared the Ebola outbreak in West Africa a Public Health Emergency of International Concern. The overall situation in the affected countries is evolving: while transmission is still widespread in Guinea and Sierra Leone, the outbreak appears to be much closer to its end in Liberia, according to WHO.
More on the Ebola outbreak