Image copyright AFP Image caption More than 240 health workers have been infected with Ebola in West Africa 
 
 Nigeria has confirmed its first Ebola death outside Lagos – a doctor in the oil hub of Port Harcourt. 
 
 His wife has been put under quarantine, while a further 70 people in the city are under surveillance. 
 
 Latest figures show more than 1,550 people have died of Ebola, with at least 3,000 confirmed cases - mostly in Guinea, Liberia and Sierra Leone. 
 
 The World Health Organization (WHO) estimates that the total number of cases could potentially exceed 20,000. 
 
 In an action plan to deal with the outbreak, the WHO said that "the actual number of cases may be 2-4 fold higher than that currently reported" in some areas. 
 
 Speaking to reporters, the WHO assistant director-general, Bruce Aylward, said the possibility of 20,000 cases "is a scale that I think has not ever been anticipated in terms of an Ebola outbreak". 
 
 He added: "That's not saying we expect 20,000... but we have got to have a system in place that we can deal with robust numbers.'' 
 
 This unprecedented outbreak is currently out of control as medical agencies struggle to cope with the increasing number of cases on the ground and continue to face hostility from communities in certain affected areas, the BBC's West Africa correspondent Thomas Fessy reports. 
 
 Before any results are seen on the ground, the number of infected people will probably continue to grow given that most treatment centres are already operating at full capacity, our correspondent adds. 
 
 Vaccine trial 
 
 West Africa's health ministers are meeting in Ghana to discuss how to tackle the world's most deadly Ebola outbreak. 
 
 Meanwhile, an international health consortium says that a trial vaccine against Ebola could be given to healthy volunteers in the UK in September, followed by trials in The Gambia and Mali. 
 
 Image copyright Getty Images Image caption Fruit bats are believed to be a major carrier of the Ebola virus but do not show symptoms 
 
 Ebola Virus Disease (EVD) 
 
 Symptoms include high fever, bleeding and central nervous system damage 
 
 Fatality rate can reach 90% - but current outbreak has mortality rate of about 55% 
 
 Incubation period is two to 21 days 
 
 There is no vaccine or cure 
 
 Supportive care such as rehydrating patients who have diarrhoea and vomiting can help recovery 
 
 Fruit bats, a delicacy for some West Africans, are considered to be virus's natural host 
 
 Ebola was taken to Nigeria by Patrick Sawyer, a Liberian-American man who travelled to Lagos before dying. 
 
 One of his contacts evaded Nigeria's surveillance team and travelled to Port Harcourt, where he sought medical treatment, Health Minister Onyebuchi Chukwu said. 
 
 Although the man later recovered, the doctor who treated him died and tests showed he had Ebola, the minister said. 
 
 The doctor had died last Friday but the results of the tests have only just been announced by the health minister. 
 
 The doctor who treated Mr Sawyer also died. 
 
 Nigeria schools shut 
 
 More than 240 health workers have been infected with Ebola - a rate which the World Health Organization (WHO) said was "unprecedented". 
 
 It noted that in many cases protective suits, even rubber gloves and face masks, were not available. 
 
 The doctor becomes the sixth fatality in Nigeria, which is Africa's most populous country. 
 
 On Wednesday, Nigeria announced that schools would not reopen until 13 October in order to try and contain the disease. 
 
 Nigerian voices: Ali Sadiq, public servant based in Abuja 
 
 "The postponement of the schools' resumption by the federal government is a good move but the extension is too long. I can't imagine my two kids wasting six more weeks at home. Two to three weeks would have been enough for all that." 
 
 Mixed reaction to Nigeria schools closure ||||| GENEVA (AP) — The World Health Organization says the Ebola outbreak in West Africa eventually could exceed 20,000 cases, more than 6 times as many as now. 
 
 A new study by the U.N. health agency also assumes that in many hard-hit areas, the actual number of cases may be two to four times higher than is currently reported. 
 
 The agency on Thursday published new figures saying that 1,552 people have now died from the Ebola virus from among 3,069 cases reported so far. ||||| More than 20,000 people could become infected with the deadly ebola virus, the World Health Organisation has said. 
 
 The UN health agency warned the actual number of current ebola cases in hard-hit areas could be 12,000 - four times higher than the number confirmed at present. 
 
 In what amounted to be a bleak assessment of the disease, the WHO said it believed the virus was still being spread in a "substantial number of localities" and added that "the outbreak continues to accelerate". 
 
 It also expressed concern at the unprecedented number of health workers who have died after treating patients in West African countries including Liberia, Guinea, Nigeria and Sierra Leone. 
 
 The WHO's assistant director-general, Dr Bruce Aylward, said: "This far outstrips any historic ebola outbreak in numbers, as the largest outbreak in the past was about 400 cases. 
 
 The outbreak has put immense strain on medical resources in West Africa 
 
 "What we are seeing today, in contrast to previous ebola outbreaks, are multiple hotspots within these countries - not a single, remote forested area, the kind of environments that have been tackled in the past. And then not multiple hotspots within one country, but international disease." 
 
 Of the 3,069 cases reported since the outbreak began, 40% of them have emerged in the past three weeks, according to the latest figures. 
 
 Its update on the outbreak came shortly after GlaxoSmithKline announced it was forming a new consortium to accelerate development of a vaccine to treat ebola. 
 
 Developed in partnership with the US National Institute of Health, it is set to be tested on healthy human volunteers within the next couple of weeks to see if it is safe and effective. 
 
 As the trials take place, the pharmaceuticals giant is set to manufacture 10,000 extra doses of the vaccine which can be used by the WHO if the clinical tests are successful. 
 
 William Pooley, a health worker, was the first Briton to contract ebola 
 
 Speaking in Geneva, the agency said it hopes to stop the spread of ebola across West Africa in the next six to nine months, with a particular focus on ensuring the virus doesn't spread internationally. 
 
 Dr Aylward said its plan will cost £300m to implement, with 12,750 health workers needed around the globe to tend to patients. 
 
 "Response activities must be adapted in areas of very intense transmission and particular attention must be given to stopping transmission in capital cities and major ports, thereby facilitating the larger response and relief effort," he added. ||||| GENEVA (Reuters) - The Ebola outbreak in West Africa has killed more than 1,552 people out of 3,069 known cases in four countries and "continues to accelerate", the World Health Organisation (WHO) said on Thursday. 
 
 The epidemic in the region, the deadliest since the disease was first discovered in 1976, has killed nearly as many people as all the previous known outbreaks combined. 
 
 "More than 40 percent of the total number of cases have occurred within the past 21 days. However, most cases are concentrated in only a few localities," the United Nations health agency said in a statement. 
 
 The WHO is later due to launch a new strategic plan for tackling the spread of the virulent disease. 
 
 A separate Ebola outbreak in the Democratic Republic of Congo, identified as a different strain of the virus, is not included in the latest figures which cover Guinea, Liberia, Sierra Leone and Nigeria. 
 
 The disease has overwhelmed West Africa's already fragile health infrastructure. On Wednesday, the head of the African Development Bank said it was causing enormous damage to the economies of the region. 
 
 (Reporting by Stephanie Nebehay; Writing by Joe Bavier; Editing by Toby Chopra and Crispian Balmer)
– Ebola cases in West Africa could multiply sixfold, affecting up to 20,000 as the virus "continues to accelerate," the World Health Organization said today, per Reuters. Some 1,552 people have now died out of the 3,069 cases reported—though the actual number of cases could be four times that amount, the AP reports. "More than 40% of the total number of cases have occurred within the past 21 days," the UN health agency said, noting an "unprecedented" number of health workers have been hit. The latest figures do not include cases in the Democratic Republic of Congo, where a different strain of Ebola is wreaking havoc. Though the majority of cases in the outbreak are in Guinea, Liberia, and Sierra Leone, the BBC reports Nigeria has seen its sixth Ebola death, and the first outside the city of Lagos, in the oil hub of Port Harcourt. To help combat the spread, pharmaceutical giant GlaxoSmithKline notes it is working with the National Institutes of Health on a vaccine to treat Ebola and will begin human trials on healthy volunteers in the coming weeks. If effective, the company will provide 10,000 doses to WHO workers, Sky News reports. Meanwhile, the WHO has revealed a new plan to tackle the virus, which includes focusing on "stopping transmission in capital cities and major ports."