Physician's assistant Jackson Niamah from Médecins Sans Frontières speaks to the United Nations Security Council in New York from Monrovia, Liberia, on 18 September. Credit: Andrew Burton/Getty

The international community is responding to the Ebola outbreak — at long last. On 18 September, the United Nations Security Council adopted a resolution declaring the outbreak a “threat to international peace and security”; two days before, the United States had said that it will send 3,000 military personnel to West Africa and spend US$750 million to support civilian efforts. Both moves are unprecedented for a disease outbreak and just what is needed, say experts. But there are fears that quelling the outbreak now will be more difficult than if it had been tackled earlier.

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The Ebola outbreak was first detected in March, but only the humanitarian group Médecins Sans Frontières (MSF, or Doctors Without Borders) has so far deployed substantial relief in the affected region, which centres on Liberia, Sierra Leone and Guinea (for more, see nature.com/ebola). MSF has repeatedly demanded that the international community launch a major effort to tackle the outbreak.

The UN resolution calls on member states to respond urgently. As it was passed, UN secretary-general Ban Ki-moon launched the United Nations Mission for Ebola Emergency Response to deploy resources from UN agencies in coordination with efforts from member nations and donors. The mission’s remit includes “stopping the outbreak, treating the infected, ensuring essential services, preserving stability and preventing further outbreaks,” said Ban.

The United States plans to establish military-run command and control headquarters in Liberia and build 17 treatment centres of 100 beds each in the affected region. It hopes to recruit medical staff to run them, and train up to 500 health-care workers a week.

The public-health community tends to view military involvement “with suspicion and mistrust”, says Adam Kamradt-Scott, a health-policy researcher at the University of Sydney in Australia. But he welcomes the US plan: “Military forces have unique skill sets that can assist civilian authorities.” If the operation does help to counter Ebola, he adds, it could set a new precedent for responding to disease outbreaks of international concern.

Training forces in outbreak response will take time, warns Daniel Bausch, who studies infectious diseases at Tulane University in New Orleans, Louisiana, and is caring for people with Ebola in Sierra Leone. He adds that the situation is too dire for the United States alone to solve, and that other nations must step in, something that the UN resolution should catalyse. It was passed by unanimous vote and had a high number of member-state sponsors.

Jean-Clément Cabrol, director of operations for MSF in Geneva, Switzerland, says that both efforts are welcome, but that the situation has worsened in the past few weeks, so speed is key. Treatment centres in the three countries most affected are completely overwhelmed (see page 474). This is fuelling the spread of the disease, because centres are forced to send away infected people, who then contaminate others.

Conventional public-health measures are no longer working, says Bausch. It has become next to impossible to detect and isolate those infected, and to monitor all the people they have been in contact with. He recommends focusing surveillance on areas next to affected zones to prevent further geographical spread of Ebola. He adds that international efforts will be effective only if they include training for health-care staff, for example in biosafety. Money and supplies are welcome, but by themselves, they are not enough.