The world is falling behind in a desperate race to gain the upper hand over the deadly Ebola outbreak, a top UN official has warned.
The three hardest-hit countries are Liberia, Sierra Leone and Guinea.
"Ebola got a head start on us," said Anthony Banbury, head of the UN Mission for Ebola Emergency Response (UNMEER).
"It is far ahead of us, it is running faster than us, and it is winning the race," he told the UN Security Council in New York, by remote link from UNMEER headquarters in Ghana.
"If Ebola wins, we the peoples of the United Nations lose so very much," he said.
"We either stop Ebola now or we face an entirely unprecedented situation for which we do not have a plan," Mr Banbury stressed.
He said that with infection rates rising exponentially every day, UNMEER will need 7,000 beds for treatment.
However, to push back the spread "we must defeat Ebola and we must do it fast," he said.
"With every day that passes, the number of sick people increases.
"Time is our biggest enemy. We must use every minute of every day to our advantage and that is what UNMEER is doing."
WHO assistant director general Bruce Aylward said the epidemic "could reach 5,000 to 10,000 cases per week by the first week of December", but described his figures as a working forecast.