The British nurse who survived Ebola told an international summit today the world must avoid 'at all cost' the 'horror and misery' of watching young children die from the disease in horrific, squalid conditions.

The Defeating Ebola conference took place in London today to tackle the epidemic, with more than 20 countries and international aid organisations pledging financial and medical help.

Visibly upset and at times overwhelmed by his emotions, Mr Pooley retold the case of a brother and sister, aged four and two, who he cared for in Sierra Leone.

He described the 'squalid' conditions they were treated in, telling how the young boy died with a pained grimace on his face lying naked in a pool of his own diarrhoea.

The little girl, described by Mr Pooley as 'beautiful', died a day after her brother, a puzzled look on her tiny face as she lay covered in her own blood.

Pleading with the world's governments, Mr Pooley, said: 'My specific fear is the horror and the misery of these deaths.

'And I just don't know what happens if that is repeated one million times and so I say, at all costs we can't let that happen.'

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British nurse, Will Pooley, who survived after becoming infected with the virus while working to help victims in Sierra Leone today made an emotional plea. He called on the international community to avoid 'at all costs' the 'horror and misery' of watching young children die from the disease in horrific, squalid conditions

Mr Pooley is pictured at the event speaking to Sierra Leone's High Commissioner to Britain, Edward Turay, centre, Mr Hammond and Justine Greening, the British International Development Secretary

Mr Pooley, from Suffolk, has just returned from a life-saving mission to the U.S. where he gave blood to try and help a victim of the virus, a friend he worked with in Sierra Leone helping victims.

The 29-year-old's emotional plea came as 34 NGOs joined forces to warn the international community they have just four weeks to stop the Ebola crisis 'spiralling completely out of control'.

The International Rescue Committee (IRC), speaking a the summit, on behalf of the six-point plan to combat 'infection rates that are growing exponentially'.

The number of cases is 'doubling roughly every three weeks', the organisations warned, as the World Health Organisation this week revealed the death toll has surpassed 3,000 in West Africa.

It comes as Save the Children warned five people are infected with the virus every hour.

And today the UN's Ebola response chief warned the longer the epidemic continues infecting people unabated, the higher the chances it will mutate and become airborne.

Anthony Banbury, the Secretary General's Special Representative, has said there is a 'nightmare' prospect the deadly disease will become airborne if it continues infecting new hosts.

His comments come as organisations battling the crisis in West Africa warn that the international community has just four weeks to stop it before it spirals 'completely out of control'

Mr Banbury told the Telegraph that aid workers were fighting a race against time amid fears it will begin to mutate.

He said: 'The longer it moves around in human hosts in the virulent melting pot that is West Africa, the more chances increase that it could mutate.

'It is a nightmare scenario, and unlikely, but it can't be ruled out.'

The International Rescue Committe, on behalf of 34 NGOs around the world, will today warn the international community there are just four weeks to stop the Ebola crisis 'spiralling completely out of control'

The organisations say there is a 'window of opportunity' to tackle the epidemic, which has killed more than 3,000 people in West Africa since the outbreak was reported earlier this year

WILL POOLEY: 'I DON'T KNOW WHAT HAPPENS IF DEATHS ARE REPEATED 1 MILLION TIMES AND SO I SAY, AT ALL COSTS WE CAN'T LET THAT HAPPEN' Visibly upset and consumed by his emotions, Mr Pooley retold the case of a brother and sister, aged four and two, who he cared for in Sierra Leone. He said 'at all costs' the international community must not allow what happened to them, be repeated one million times. He said: 'They were on a specific ward alone, their mother and father had probably died. 'The blood results came back and they were both positive for Ebola, so I took them both by the hand and led them down the muddy track on to the confirmed ward. 'They were both quite weak and they struggled their way through the puddles and the mud on to the ward, squalid ward B in Kenema. Mr Pooley, 29, said the world must not let the horrific deaths of two tiny children in Sierra Leone be repeated a million times over, as he pleaded with governments to help tackle the crisis. Pictured, a health worker lifts a young victim at a medical centre in West Africa 'I popped them up on to a bed, they shared. The boy had diarrhoea and he was very weak, too weak to get up so he soiled himself. 'I cleaned him up as best I could with the limited materials available and removed his dirty clothes. 'Thereafter he lay naked on the bed, there was nothing to change him into or cover him with, the diarrhoea trickling out of him. 'His sister looked on and I encouraged her to help him take fluids regularly, she was also very weak and she tried her best. 'The next morning I came in and saw him lying as I had left him, on the bed. 'He wasn't breathing. I remember going up to him and looking at his face, his lips were drawn back in a grimace, and his eyes were vacant, lying in a pool of his own diarrhoea. 'I lifted his hand to try, just to confirm things and his whole body turned rigid and cold. 'I put him in a body bag as his sister looked on. 'She seemed more baffled than anything, not really understanding what was happening. I carried his corpse outside with the others. 'The little girl, she deteriorated the next day. Overnight, the following night she had intravenous fluids and the line came out and she bled. 'I came in the following morning and she was covered in blood. She still had a very puzzled expression on her face and she wasn't breathing. 'So I put her in a bag and left her next to her brother. She was a beautiful little girl.' Fighting back tears, Mr Pooley added: 'So my specific fear is that the horror and the misery of these deaths really fill a hole in my despair. 'And I just don't know what happens if that is repeated one million times and so I say, at all costs we can't let that happen.' Advertisement

Foreign secretary Philip Hammond is co-chairing the Defeating Ebola conference in London today, where more than 20 countries will pledge their help to tackle the crisis

More than 20 countries from around the world, including the U.S., Australia, New Zealand, Japan, France, Spain, and Sierra Leone, Guinea, Ghana and Nigeria are taking part

Save the Children has warned five people are infected with the virus, seen under the microscope, every hour

This week the first case of Ebola on U.S. soil was diagnosed after Thomas Eric Duncan flew into Dallas, Texas from Liberia, touching down in Brussels and Washington en route.

Foreign secretary Philip Hammond is co-chairing the conference at Lancaster House today, attended by representatives from Sierra Leone, Guinea, Liberia, Ghana, Nigeria, the U.S., France, Spain, Cuba, Netherlands, Japan, China, Sweden, Switzerland, Australia, New Zealand, Canada, Finland, Belgium and the EU.

The conference aimed to highlight the scale of the crisis, and call on the countries taking part to pledge their support to tackling the crisis.

The longer it moves around in human hosts in the virulent melting pot that is West Africa, the more chances increase that it could mutate - UN Ebola response chief

As the nations taking part made pledges of the help they can offer, it emerged Save The Children will donate £70 million to the fight and Comic Relief, a further £1 million.

Cuba has promised to send 63 doctors and 102 nurses to Sierra Leone, while Australia has pledged $10 million and Finland too, has promised financial support.

Mr Hammond hailed Mr Pooley, as an example of the 'courage' and resilience needed to tackle the Ebola crisis.

Mr Pooley, 29, is just back from a life-saving mission to the United States where he gave blood to try to help a victim of the virus.

Speaking at a press conference during the international summit, Mr Hammond said: 'His body has considerable immune cells in the hope of helping to advance research into finding a vaccination against the disease.

'Yesterday he was helping to train health workers about to deploy to the region. Today he has been here acting as an ambassador for the crusade against Ebola at this conference.'

Mr Pooley became the first Briton to contract the virus after working as a volunteer nurse in Sierra Leone, which is one of the worst-hit countries of the current outbreak.

He was flown back to Britain on August 24 and recovered after being treated at an isolation unit at London's Royal Free Hospital.

Actor Idris Elba, whose father was born in Sierra Leone, is also attending today's Defeating Ebola summit, pledging his support to tackling the crisis, pictured with Justine Greening

International Development Secretary Justine Greening said: 'The picture painted by Will Pooley of his experience and the children he had cared for but who nevertheless died gave us a real sense of what this disease is doing to families and to people on the ground.'

Sanjayan Srikanthan, of the International Rescue Committee, told delegates the world has a 'window of opportunity' to quash the spread of the disease.

WHAT HELP IS NEEDED? At today's Defeating Ebola conference, Mr Hammond will ask the international community to pledge help as well as financial assistance to the UN Trust Fund. In addition he asked for: Infection prevention and control experts for training and supervision

Information management and geographic information systems

Support for essential commodities

Help to maintain sufficient air support for personnel and supplies

Help to meet medevac requirements for international staff infected with Ebola

Primary and secondary health care (non-Ebola) for international staff Advertisement

He spoke on behalf of 34 organisations, including Christian Aid, Médecins du Monde, Oxfam, Samaritan's Purse and Save the Children - many of whom have aid workers on the ground in the worst affected regions.

Mr Srikanthan, warned : 'Like chasing a ball down a hill, every day that we delay in disbursing resources to affected countries, the more impossible it becomes to contain the disease.'

In a statement prepared for the summit, he said: 'The international community has a window of opportunity over the next four weeks to stop the crisis from spreading completely out of control.

'To do so, we must support national authorities, health workers, humanitarian agencies and community groups to break transmission rates and halt the exponential increase in cases.'

Experts from the WHO and Imperial College, London predict numbers will continue to climb and more than 20,000 people will have been infected by early November.

So far, around 6,500 cases have been officially recorded, though the number of victims is thought to be under reported.

Mr Srikanthan echoed the pictured painted by Mr Pooley.

He said the situation in Sierra Leone, one of the worst affected nations, is 'critical'.

British actor Idris Elba greets development secretary Justine Greening on the steps of Lancaster House

Dr Bruce Aylward from the World Health Organisation, left, and Justine Greening at the Ebola conference

Foreign secretary Mr Hammond and Ms Greening speak at a press conference following the Defeating Ebola in Sierra Leone summit at London's Lancaster House

Mr Hammond speaking to the media ahead of the meeting, which saw representatives from more than 20 countries across the world

'Ebola has spread throughout the country, infecting at least 2,300 people that we know of; the real number is probably much higher,' he said.

'Many health centres and hospitals have closed and those that are still open are full to capacity, with sick people being turned away.

'As I speak, our agencies have hundreds of staff on the ground fighting the spread of the disease.

'We are involved in every aspect of response from treatment to provision of equipment to body disposal and prevention and awareness raising, as well as dealing with secondary impacts like food security.

'We also have dedicated teams working in neighbouring countries to prepare for the worst case scenario.

'Our staff say they are fighting for the very survival of their communities.'

He said the IRC welcome the 'strong commitment' demonstrated by many Governements already, in responding to the crisis.

But, he said, a 'further and massive increase in financial, human and material capactiy' is urgently needed to halt the spread of Ebola and mitigate its impacts on the nations affected.

'This is a matter of the utmost urgency,' he said.

He added: 'We can turn the tide on this outbreak today.

'As aid agencies and campaigning organisations, we are all scaling up our work, doing all we can to support the people affected by Ebola. But we need your help.

'The international community needs to move faster than it has ever moved before to prevent a catastrophe in West Africa with global implications.

'Every new case is a testament to how much more we still need to do, and we are running out of time.'

US EBOLA PATIENT HELPED CARRY CONVULSING PREGNANT WOMAN JUST FOUR DAYS BEFORE HE FLEW FROM LIBERIA TO TEXAS Officials confirmed this week the first patient has been diagnosed with the deadly disease on U.S. soil. Thomas Eric Duncan flew back into the U.S. on September 20 from Liberia, touching down in Brussels and Washington en route. It emerged just four days before Mr Duncan boarded a plane bound for Dallas, Texas, he helped carry his landlord's convulsing daughter to a Liberian clinic to be treated for Ebola. The woman, named by the New York Times as 19-year-old Marthalene Williams died the next day, after being turned away from the overcrowded hospital that didn't have room for her.

Thomas The landlord's son and three neighbors who came in contact with the woman also died soon afterwards. But Mr Duncan wasn't showing any symptoms when he arrived at a Monrovia airport on September 19, and therefore was allowed on a flight out of Liberia bound for the U.S. Current policy dictates that only those displaying symptoms of the disease are barred from flying. But Ebola can hide in the system for up to 21 days, raising serious concerns the disease will start turning up around the world. In Liberia, Mr Duncan worked moving cargo for FedEx, but had recently quit his job when he acquired a visa to visit the U.S. where his son reportedly lives. He is one of an estimated 13,500 people from the Ebola hot-spot countries of Sierra Leone, Guinea and Liberia who currently hold visas to visit the U.S. and could possibly spread the outbreak. However, that estimate takes into account all people from these West African countries who are already in the U.S., and those who have been to America and since returned home. It's still uncertain the exact number of visas waiting to be used for travel to the U.S. Advertisement

The conference will aim to highlight the scale of the crisis, and call on the countries taking part to pledge their support to tackling the crisis

Experts from the WHO and Imperial College, London predict numbers will continue to climb and more than 20,000 people will have been infected by early November

So far, around 6,500 cases have been officially recorded, though the number of victims is thought to be under reported

Ebola is not contagious until symptoms begin, and it takes close contact with bodily fluids to spread

U.S. EBOLA PATIENT CAME IN CONTACT WITH HUNDREDS DURING THREE FLIGHTS FROM LIBERIA TO TEXAS United Airlines has released two of the flight numbers for planes Ebola patient Thomas Eric Duncan reportedly traveled on during his trip to the US. The airline said in a Wednesday statement it believed Duncan was on board both Flight 951 - from Brussels to Washington Dulles International Airport - and Flight 822, which would have taken him from there to Dallas/Fort Worth International Airport. CBS DFW reported that after some digging, one of its news teams 'believes there is a good chance the Ebola infected patient left Liberia on Brussel Airlines flight 1247.' The above map shows the reported flight plan Mr Duncan took from Monrovia, Liberia all the way to Dallas, Texas where he eventually started showing signs of Ebola last week Conservative news blog Gotnews.com published an email from someone claiming to work for United Airlines, which allegedly details the man's trip and claimed Duncan was on Brussels Airlines Flight 1247. The alleged email also claims that Duncan planned to return to West Africa in approximately two weeks. Currently, patients are checked for fever - the first sign of a possible infection - before they are allowed to board flights leaving West African nations. However, once travelers gets past examiners in Liberia, Sierra Leone or Guinea, there are few barriers to them moving across the world. U.S. Customs and Border Protection says the agency's examiners at airports and other ports of entry are trained to spot and identify people potentially infected with Ebola before they enter the country. Advertisement

Speaking yesterday ahead of the 'Defeating Ebola' conference Mr Hammond, called for countries to increase financial aid as well as other vital help including medical expertise, transport and supplies.

'We need help from the international community to provide us with the doctors and nurses, so we're asking other countries to piggy back on the structure we've put in place,' he said.

'Britain's got a footprint on the ground in Sierra Leone, we've got military engineers there, we've got a big DFID presence, we've got a plan to roll out a large number of additonal Ebola treatment beds,' he said.

WHAT IS THE EBOLA VIRUS? The CDC says 'Ebola was first discovered in 1976 near the Ebola River in what is now the Democratic Republic of Congo' Four types of Ebola can make people sick, the agency says Ebola symptoms can include fever, muscle pain, vomiting and bleeding, and can appear as long as 21 days after exposure to the virus Ebola is not contagious until symptoms begin, and it takes close contact with bodily fluids to spread Liberia is one of the three hardest-hit countries in the epidemic, along with Sierra Leone and Guinea The epidemic has killed more than 3,000 people in West Africa People boarding planes in the outbreak zone are checked for fever, but that does not guarantee that an infected person won't get through Source: cdc.gov/Includes AP text Advertisement

Although WHO said the total number of new cases had fallen for a second week, it warned of under-reporting and said there were few signs of the epidemic being brought under control.

'Transmission remains persistent and widespread in Guinea, Liberia and Sierra Leone, with strong evidence of increasing case incidence in several districts,' a WHO spokesman said.

The Save the Children charity warned the authorities faced the prospect of an epidemic 'spreading like wildfire' across Sierra Leone, saying there had been 765 new cases reported in the country last week but there were only 327 beds available.

'The scale of the Ebola epidemic is devastating and growing every day, with five people infected every hour in Sierra Leone last week,' the charity's chief executive, Justin Forsyth, said.

'We need a coordinated international response that ensures treatment centres are built and staffed immediately.'

He told BBC Radio 4's Today Programme: 'We need urgent action - we've had some money pledged, but not enough, and only one per cent has got there on the ground.

'And also we need to coordinate between all the different players. We're in a race against time, we need to act very, very quickly on the ground.

'We're helping with the MoD and DfiD build a treatment centre outside Freetown. People are queuing up outside treatment centres and dying outside.

'There are only 51 doctors in Liberia and 1,000 nurses for four million people. They're not going to have enough people on the ground. The world, if it has the will, can make a difference.'

Although the charity praised UK efforts, a British parliamentary committee said on Thursday that cuts in aid from Britain to Libera and Sierra Leone had compromised the fight against the disease.

'In the midst of this devastating epidemic... it is wrong for the UK to cut its support to these two countries by nearly a fifth,' International Development Committee chairman, Malcolm Bruce, said in a report from the committee.

'The planned termination of further UK funding to the Liberian health sector is especially unwise.'