The Ebola outbreak in West Africa could spread to hundreds of thousands more people by the end of January, according to an estimate under development by the U.S. Centers for Disease Control and Prevention that puts one worst- case scenario at 550,000 or more infections.
The report, scheduled to be released next week, was described by two people familiar with its contents who asked to remain anonymous because it isn't yet public.
The projection, which vastly outstrips previous estimates, is under review by researchers and may change. It assumes no additional aid or intervention by governments and relief agencies, which are mobilizing to contain the Ebola outbreak before it spirals further out of control in Liberia, Sierra Leone and Guinea.
"CDC is working on a dynamic modeling tool that allows for recalculations of projected Ebola cases over time," Barbara Reynolds, a spokeswoman for the agency, said in an e-mail. "CDC expects to release this interactive tool and a description of its use soon."
The World Health Organization said last month that the outbreak could reach 20,000 cases before being brought under control. That projection is already outdated, WHO spokesman Dan Epstein said Friday in a phone interview.
"In the three weeks since then, the numbers have doubled so all three countries are still reporting cases on a steep upward curve," Epstein said. "We don't have a good idea of how big this epidemic will become."
If the response is not increased, there may be as many as 5,000 new cases a week, he said.
A nationwide three-day curfew in Sierra Leone entered its second day Saturday as part of a government effort to stop the virus from spreading. During the lockdown, almost 30,000 volunteers go door to door to distribute soap and explain Ebola prevention measures.
Volunteers removed seven corpses yesterday from houses in the capital Freetown, Mohamed Bangura, a supervisor of the public awareness campaign, said by phone. Health authorities registered 33 new cases and six deaths yesterday, bringing the total number of confirmed Ebola cases to 1,618, according to the Emergency Operations Center.
The WHO's estimates are meant to help assess international relief needs, such as how many hospital beds to build and the amount of medical supplies needed. The U.S. is currently adding personnel and money to the effort.
'Not Nearly Enough'
"It's already the worst outbreak in history," Tim Shenk, a spokesman for the humanitarian group Doctors Without Borders, said in a phone interview. He said the actions of the U.S. government will determine whether the growing epidemic can be contained.
"What we've been clear about is that we are doing everything we can do and it's not nearly enough," Shenk said.
Since the start of the outbreak this year, the virus has infected 5,357 people, killing 2,630, according to a Sept. 18 WHO report. The disease has spread through five West African countries, accelerating in cities including Monrovia, the capital of Liberia.
The United Nations announced Friday the creation of a special emergency mission to respond to the crisis, saying the effort needs to increase greatly.
"This is a disease outbreak that is advancing in an exponential fashion," said David Nabarro, named special envoy to West Africa by UN Secretary-General Ban Ki-Moon. "I estimate that to get ahead of outbreak, the level of response needs to be about 20 times greater than it is at the moment."
The U.S. is intensifying its effort, planning to deploy about 3,000 U.S. military personnel to the region to assist with shipping and distributing medical supplies and building treatment centers.
Major General Darryl Williams, U.S. Army-Africa commander, arrived in Monrovia on Sept. 17 with a 12-person team to assess the situation there, Rear Admiral John Kirby, a Pentagon spokesman, said Friday at a news conference. That includes deciding where to build treatment sites and what else will be needed from the U.S. military.
One C-17 transport plane has already arrived, and two more are scheduled for next week, bringing 45 personnel and helping to set up a command headquarters, Kirby said.
'Sense of Urgency'
Asked about the CDC projection, White House press secretary Josh Earnest said the U.S. commitment of $1-billion for the response to Ebola will have the effect of spurring other nations to increase their assistance.
"The projections you're citing are long-term projections," Earnest said Friday. "That's why the president was demonstrating a sense of urgency" when he spoke about the outbreak earlier this week.
Predictive models have varied as researchers struggle to estimate an outbreak on a size and scale never seen before with Ebola.
A separate worst-case scenario modeled last month by researchers at the University of Tokyo and Arizona State University predicted there would be as many as 277,124 new cases by the year's end.
That was the high end of their estimate though the researchers warned that "uncontrolled cross-border transmission could fuel a major epidemic to take off in new geographical areas."
Ebola 'Transmission Dynamics'
Columbia University researchers predicted 18,755 cases by Oct. 26 if the situation didn't change, and 49,129 if intervention and containment efforts degraded.
"Our understanding of Ebola transmission dynamics is incomplete and data on the present outbreak are limited," the researchers said.
Curbing the outbreak will require investments of $988-million over the next six months, according to an overview of needs and requirements published by the UN. About 30 per cent of what's needed has come in so far, Nabarro said this week at a briefing in Geneva.
There is no cure for Ebola, which is spread by contact with the blood and bodily fluids of those infected. The disease normally is treated by keeping patients hydrated, replacing lost blood and using antibiotics to fight infections. The hope is that a patient's immune system will fight off the aggressive attack of the virus.
Several companies and government health authorities are testing experimental treatments and vaccines against the disease.