In March 2014, the World Health Organization (WHO) announced that health officials in Guinea had identified a "rapidly evolving outbreak of Ebola virus disease (Ebola)." Retroactive studies indicated that the virus had likely begun to spread in late December 2013, but that weak disease detection and surveillance systems had failed to identify the outbreak. From Guinea, the disease spread to Liberia and Sierra Leone and continued to infect thousands in the three countries until mid-2015, when concerted efforts to contain the disease by the international community began to curb new infections and deaths. WHO declared Ebola a Public Health Emergency of International Concern (PHEIC) in August 2014. By then, the disease had reached Nigeria, had infected 1,779 people, and had claimed 961 lives. Some groups, including Doctors Without Borders, criticized WHO for the delayed designation. Following the PHEIC declaration, the United States and other actors exerted a concerted effort to contain the disease, and cases began to decline rapidly. As an indication of a reversal in the trend, some 950 people in West Africa contracted Ebola each week in September 2014. By July 2015, average weekly cases fell to five. On December 29, 2015, the fight against the West Africa Ebola outbreak reached a pivotal point. WHO declared that human-to-human Ebola transmission had ended in Guinea, marking the first time all three countries had stopped the original chains of transmission at the same time. Liberia had stopped transmission two weeks earlier and Sierra Leone had interrupted transmission in November 2015. By this time, WHO had reported 28,637 confirmed, probable, and suspected Ebola cases worldwide, including 11,315 deaths. Although WHO had declared that the outbreak had ended in Guinea, the organization cautioned that small outbreaks could occur. Since that pivotal moment in December 2015, WHO has reported 19 more cases, including 8 deaths. All but 15 of the 11,323 Ebola-related deaths that have occurred worldwide were contracted in Guinea, Liberia, and Sierra Leone. In September 2014, one month after WHO characterized Ebola as a PHEIC, Congress enacted legislation ( P.L. 113-164 , Continuing Appropriations Resolution, 2015) that provided $88 million for a U.S. Ebola response: $30 million for U.S. Centers for Disease Control and Prevention (CDC) Ebola response activities in West Africa and $58 million for research and development of specific treatments and vaccines for Ebola, to remain available until September 30, 2015. Congress had also permitted the Department of Defense (DOD) to reprogram roughly $750 million of FY2014 Overseas Humanitarian Disaster and Civic Aid (OHDACA) funds to build Ebola treatment units (ETUs) in Liberia and support ongoing U.S. efforts in the region. In October 2014, President Barack Obama announced that the United States would launch a "whole-of-government" response to the Ebola outbreak, which would include deploying the U.S. military to construct up to 17 ETUs in West Africa. One month later, the Administration submitted a $6.2 billion budget request to fund the plan, which included $1.5 billion for a Contingency Fund. In December 2014, Congress enacted the Consolidated and Further Continuing Appropriations Act, 2015 ( P.L. 113-235 ), providing several federal departments and agencies $5.4 billion in FY2015 emergency supplemental appropriations for the U.S. government Ebola response. Since these funds are emergency spending, they were effectively exempt from spending limits, per the Budget Control Act of 2011 (BCA, P.L. 112-25 ). Of the funds Congress appropriated for international Ebola responses, roughly half were provided to the Department of State and the U.S. Agency for International Development (USAID) through Title IX, Division J of P.L. 113-235 ( Figure 1 ). The foreign affairs funds, which totaled more than $2.5 billion, were limited to use for the Ebola response, although the law permitted funds from some accounts to be used for preparedness efforts in countries "at risk of being affected by" the outbreak, such as Mali and Nigeria (which both experienced imported Ebola cases). Section 9001 authorized the Secretary of State and the USAID Administrator to make certain transfers of funds between accounts within Title IX, albeit only for Ebola-related purposes, and with a 15-days-in-advance written congressional notification to the appropriations committees. As of March 1, 2016, the Department of State and USAID have obligated (or committed) less than half of the $2.5 billion international Ebola emergency funding ( Table A-1 ). USAID organized Ebola response activities into four pillars ( Table A-2 ). Almost 70% of the Ebola funds were aimed at Pillar 1: controlling the outbreak ( Figure A-1 ). In January 2016, USAID disbanded its Disaster Assistance Response Team (DART) in West Africa, which had coordinated the whole-of-government U.S. response to the Ebola outbreak. Under the DART, each agency led particular parts of the response. For example, USAID managed and coordinated U.S. international Ebola responses; CDC led the medical and public health components; the National Institutes of Health (NIH) conducted and supported research and development of new Ebola diagnostic, treatment, and preventive tools; and the Department of State advanced diplomatic efforts. Other department and agencies also provided support for specific purposes. The DOD, for example, deployed nearly 3,000 troops to the region who constructed ETUs. Other U.S. officials posted temporarily to the region included more than 1,000 CDC personnel and 465 USAID staff. U.S. agencies have collaborated in West Africa to procure rapid Ebola diagnostic tests; support contact tracing; construct ETUs to facilitate the isolation of Ebola patients and fund community care centers; train thousands of health care workers on how to screen individuals for potential Ebola signs and symptoms and how to implement contact tracing programs; provide mobile laboratories and open new laboratory testing facilities in the region to increase; diagnostic capacity; promote coordination, operations, and communication efforts surrounding the response; and support the operation of emergency operations centers, safe burial teams, and health care systems in West Africa. Ebola control efforts in West Africa are in Phase 3, characterized by limited transmission across small geographic areas and low probability of large-scale Ebola outbreaks. In Phase 1, WHO and implementing partners, including the United States, focused on isolating and treating Ebola cases and ensuring safe burial of all Ebola deaths. During Phase 2, responders emphasized disease surveillance, contact tracing, and community engagement. The marked decline in cases that occurred during the second phase signaled a transition to the third phase. On March 1-2, 2016, WHO convened a meeting with stakeholders, including USAID and CDC, to assess Ebola control efforts in Guinea, Liberia, and Sierra Leone. At the meeting, health officials from the three countries "expressed confidence in the capacity…to effectively manage residual risks of new Ebola infections—pointing to the rapid government-led containment of recent flare-ups of the disease." Since the primary Ebola outbreak ended in December 2015, the three countries have successfully led collaborative efforts to contain small outbreaks. Representatives from the three countries also highlighted increased efforts to utilize cross-country cooperative approaches for Ebola control. In March 2016, for example, Guinean, Liberian and WHO officials along with other partners identified and contained a small outbreak, which caused 13 suspected cases in Guinea and Liberia (the outbreak originated in Guinea and was imported into Liberia). In response to the March 2016 outbreak, local Guinean health authorities reactivated the emergency coordination mechanism that was instituted at the height of the Ebola epidemic to manage an inter-agency response, which included the deployment of 75 WHO epidemiologists, surveillance experts, contact tracers, vaccinators, social mobilizers, health promoters, and infection prevention and control experts. The interagency team also included non-governmental organizations, which provided food packages, hygiene kits, and cash stipends to the more than 1,000 contacts who had been identified and placed under medical observation. More than 1,500 people have been vaccinated with the experimental Ebola vaccine VSV-EBOV to contain the March 2016 flare-up. The vaccine was developed by NewLink Genetics and Merck Vaccines USA in collaboration with the Public Health Agency of Canada. A large clinical trial conducted in 2015 by the Guinean Ministry of Health, WHO and implementing partners, including NIH, demonstrated that it was highly effective at preventing Ebola infection. The "ring vaccination" strategy, which involves vaccinating anyone who has come into contact with an Ebola-infected person, as well as their own contacts, has become part of standard operating procedures when responding to Ebola flare-ups. According to a March 2016 report by the Inspectors General of USAID and U.S. Department of Health and Human Services (HHS), USAID and CDC have carried out a number of efforts to restore primary health services in the affected countries. In Guinea, for example, the U.S. government supported the restoration of basic health services at 90 facilities by supporting IPC training for over 2,800 health care workers. USAID supported the development of infection prevention and control (IPC) training curriculum, conducted IPC training, and supervised health practitioners to ensure adherence to IPC protocols, while CDC aided in the development of a national IPC policy and strategy and supported IPC action plans in recently affected prefectures. These activities have been conducted in addition to the substantial initiatives U.S. agencies carried out to identify, treat and isolate Ebola patients during the height of the epidemic. The Appendix includes additional examples of U.S. support for restoring health services in the three countries. Due to the precipitous decline in new cases towards the end of 2015, the United States has reduced funding for Phase 1 and Phase 2 types of activities.