West Africa's Ebola outbreak is an "extraordinary event" and a public health risk to other states, according to a new statement from the World Health Organization (Geneva). The agency said the possible consequences of a further international spread of the outbreak, which has killed almost 1,000 people in four West African countries, were "particularly serious in view of the virulence of the virus, the intensive community and health facility transmission patterns, a coordinated international response is deemed essential to stop and reverse the international spread of Ebola." .