The World Health Organisation (WHO) has said the number of people killed by Ebola in West Africa has exceeded 11,250.A total of 27,643 cases of the Ebola virus disease (EVD) have been reported since the outbreak of the disease, TASS reported on Friday.The maximum number of Ebola-related deaths has been registered in Liberia (4,806 deaths and 10,666 total cases) in the country while the average death rate is 50 percent. Liberia is followed by Sierra Leone (3,947 deaths) and Guinea (2,506 deaths) respectively.Separate cases have also been registered in Mali, Nigeria, Senegal, Spain, Britain and the United States.The EVD is a severe illness in humans, often fatal. The virus is passed on to people from wild animals and can be transmitted from humans to humans. Early supportive care, which includes rehydration and symptomatic treatment, improves the survival rate.There are no licensed Ebola vaccines yet but two candidates are being evaluated.