U.S. President Barack Obama on Thursday called on more nations to help fight the world's worst outbreak of the deadly Ebola virus, saying hundreds of thousands of lives were at stake.
The warning came shortly after the World Health Organisation gave a rare hint of optimism in the West African crisis, announcing that the spread of the disease in Guinea appeared to have stabilised.
Sierra Leone put three more districts -- home to over a million people and major mining operations -- under indefinite quarantine.
An outbreak that began in a remote corner of Guinea has taken hold of much of neighbouring Liberia and Sierra Leone, killing nearly 3,000 people in just over six months. Senegal and Nigeria have recorded cases but, for now, contained the spread of Ebola.
"More nations need to contribute critical assets and capabilities -- whether it's air transport, medical evacuation, health care workers, equipment or treatment," Obama told a meeting on Ebola on the sidelines of the U.N. General Assembly.
"If unchecked, this epidemic could kill hundreds of thousands of people in the coming months."
Weak health systems have been overrun by one of the deadliest diseases, and reliable information on its spread is scarce. But most experts warn that the number of cases recorded so far represents a fraction of the true total, with many victims unable or unwilling to come forward for treatment.
WHO said earlier this week the total number of infections could reach 20,000 by November, months earlier than previously forecast. The U.S. Centers for Disease Control and Prevention (CDC) warned between 550,000 and 1.4 million people might be infected in the region by January if nothing was done.
The United States is deploying 3,000 soldiers to build treatment centres and train local medics. Other nations, including Britain, France, China and Cuba, have pledged military and civilian personnel alongside cash and medical supplies.
The World Bank has said it will give an additional $170 million to support medics and healthcare systems in the region.
"The reality on the ground today is this: the promised surge has not yet delivered," said Joanne Liu, international president of Medecins Sans Frontieres, a medical charity that has been treating patients in the region for months.
Speaking at the same meeting as Obama in New York, Liu said the sick were desperate, aid workers were exhausted and infection rates were doubling every three weeks.
"Our 150-bed facility in Monrovia opens for just thirty minutes each morning. Only a few people are admitted -- to fill beds made empty by those who died overnight," she said.
In one of its regular briefings on the crisis, the WHO said Guinea offered a ray of hope.
"The upward epidemic trend continues in Sierra Leone and most probably also in Liberia," it said.
"However, the situation in Guinea, although still of grave concern, appears to have stabilized: between 75 and 100 new confirmed cases have been reported in each of the past five weeks."
Overnight, Sierra Leone's President Ernest Bai Koroma announced the districts of Port Loko and Bombali in the north and Moyamba in the south would be quarantined. Five of the country's 14 districts have now been quarantined.
"The isolation of districts and chiefdoms will definitely pose great difficulties for our people in those districts," Koroma said. "(But) the life of everyone and the survival of our country take precedence over these difficulties."
Under the new measures, people will be able to travel through quarantined districts during daylight hours so long as they do not stop. The World Food Programme is meant to provide food to residents living there.
The Ebola outbreak comes a decade into Sierra Leone and Liberia's recovery from civil wars that killed hundreds of thousands of people in the 1990s.
Since then both nations have secured billions of dollars in investment, especially from mining firms looking to tap into their vast iron ore reserves.
But border closures and travel bans caused by Ebola have hamstrung trade.
Iron ore miner African Minerals has rail and port services in Port Loko district but the company said it had not been impacted in any way by the new restrictions.
London Mining, which operates in the area too, did not have an immediate comment.
Axel Addy, Liberia's minister for commerce and industry, said his nation had secured imports of basic food staples until December, but the blow to its mining sector may trigger a recession next year.
A Spanish priest who caught Ebola in Sierra Leone has died after being repatriated, Spanish authorities said.
Distrust of outsiders
Ebola spread slowly at first but warnings of exponential spread in recent weeks have spooked international leaders into pledging more action.
But the crisis appears to be outpacing the response.
The WHO said Liberia had 315 bed spaces for Ebola patients and aid agencies had promised to set up 440 more, but the country needs a further 1,550. In Sierra Leone, 297 planned new beds would almost double existing capacity, but a further 532 were needed.
The lack of beds means many people infected with Ebola are being turned away from hospitals and must be cared for at home, where they risk infecting yet more people.
As a result, part of the aid response is focusing on setting up care centres in communities and training locals, including 11,000 teachers in Liberia, to educate people about how to combat the disease.
The first 9,000 of a planned 50,000 kits -- containing protective gowns, gloves and masks for family members to look after Ebola sufferers -- arrived in Liberia.
WHO said such efforts were still being resisted in remote communities with a distrust of outsiders, like the one where local people killed eight members of an Ebola team in southeast Guinea last week.
"There are reports from Fassankoni, Guinea, that communities have set up roadblocks to screen entering response teams," it said.