By Elise Viebeck - 09/03/14 12:05 PM EDT
The head of the World Health Organization (WHO) called Ebola a "global threat" and warned that it can only be stopped by a significant international response.
Margaret Chan, the director general of WHO, did not mince words in describing the growing epidemic in West Africa on Wednesday.
"It has become a global threat that requires urgent action. ... This is an international issue, a global threat, and it requires a coordinated effort."
According to WHO, it will cost at least $600 million to contain the outbreak.
Chan's comments come as the United Nations remains under fire for its response to Ebola, which has killed at least 1,900 people in West Africa since March.
In an op-ed this week, World Bank President Jim Yong Kim called the containment effort "disastrously inadequate" and said it is causing "needless" deaths.
U.N. officials have confirmed at least 3,500 cases of Ebola virus disease in the three countries where it is concentrated — Guinea, Sierra Leone and Liberia — and that number is rising daily. The disease has an overall fatality rate of 51 percent.
Warnings from U.S. and international health officials have grown increasingly dire as the disease evades efforts to contain it and as public unrest increases on the ground.
Tom Frieden, director of the Centers for Disease Control and Prevention, said Tuesday that the epidemic is "spiraling out of control," a marked change in tone from his comments early last month.
"It's bad now, and it's going to get worse in the very near future. There is still a window of opportunity to tamp it down, but that window is closing. We really have to act now," Frieden said on CBS.
International health workers echoed those remarks on Wednesday.
"We are not in a position where we can afford to lose a day because this outbreak is currently moving ahead of efforts to control it," said David Nabarro, Senior U.N. System Coordinator for Ebola.
WHO is currently leading the response to the epidemic alongside the U.S. government and outside groups.
But officials described their role as "providing advice" to the affected countries, which are technically in charge of stopping the disease from spreading.
The most pressing need is for a surge of healthcare workers and equipment on the ground, as much as three or four times the current number of personnel, Nabarro said.
Without a swift increase in response, the virus "really does get very hard to control," he added.
U.N. officials have declined to endorse sending military troops to the affected countries to help control the epidemic, despite urging from doctors there.
Countries where the virus is concentrated would not accept a "takeover" by the international community, Chan said.
The head of Doctors Without Borders pressed the U.N. earlier this week to step up its response.
"Six months into the worst Ebola epidemic in history, the world is losing the battle to contain it," Dr. Joanne Liu told member states.
"It is imperative that states immediately deploy civilian and military assets with expertise in biohazard containment. ... Without this deployment, we will never get the epidemic under control."