Ebola Outbreaks 2000-2014
2014: Ebola Hemorrhagic Fever Outbreak in West Africa (Guinea, Liberia, Sierra Leone, and Nigeria)
The 2014 Ebola outbreak is one of the largest Ebola outbreaks in history and the first in West Africa. It is affecting four countries in West Africa: Guinea, Liberia, Nigeria, and Sierra Leone, but does not pose a significant risk to the U.S. public. CDC is working with other U.S. government agencies, the World Health Organization, and other domestic and international partners in an international response to the current Ebola outbreak in West Africa. CDC has activated its Emergency Operations Center (EOC) to help coordinate technical assistance and control activities with partners. CDC has deployed several teams of public health experts to the West Africa region and plans to send additional public health experts to the affected countries to expand current response activities.
Latest CDC Outbreak Information
Updated August 28, 2014
Updated August 28, 2014
As of December 2, 2012, the Ugandan Ministry of Health reported 7 cumulative cases (probable and confirmed) of Ebola virus infection, including 4 deaths, in the Luwero District of central Uganda. CDC assisted the Ministry of Health in the epidemiologic and diagnostic aspects of the outbreak. Testing of samples by CDC's Viral Special Pathogens Branch took place at the Uganda Virus Research Institute in Entebbe. Reported numbers are subject to change.
The DRC Ministry of Health has declared an end to the most recent Ebola outbreak in DRC's Province Orientale. The November 26 Press Release reports a final total of 77 cases, including 36 laboratory-confirmed cases, 17 probable and 24 suspect cases, with a total of 36 deaths. CDC assisted the Ministry of Health in the epidemiologic and diagnostic aspects of the investigation. Laboratory support was provided both through CDC's field laboratory in Isiro, and through the CDC/UVRI lab in Uganda. The Public Health Agency of Canada (PHAC) also provides diagnostic support through its field lab in Isiro. The outbreak in DRC has no epidemiologic link to the near contemporaneous Ebola outbreak in the Kibaale district of Uganda. Reported numbers are subject to change.
On July 28, 2012, the Uganda Ministry of Health reported an outbreak of Ebola Hemorrhagic Fever in the Kibaale District of Uganda. A total of 24 human cases (probable and confirmed only), 17 of which were fatal, were reported starting at the beginning of July. Laboratory tests of blood samples, conducted by the Uganda Virus Research Institute (UVRI) and the U.S. Centers for Disease Control and Prevention (CDC), confirmed Ebola virus in 11 patients, four of whom died. Reported numbers are subject to change.
On October 4, 2012, the Uganda Ministry of Health declared the outbreak ended.
On May 14, 2011, the Ugandan Ministry of Health informed the public that a patient with suspected Ebola Hemorrhagic fever died on May 6, 2011 in the Luwero district, Uganda. CDC-Uganda confirmed a positive Ebola virus test result from a blood sample taken from the patient. The quick diagnosis of Ebola virus was provided by the new CDC Viral Hemorrhagic Fever laboratory installed at the Uganda Viral Research Institute (UVRI).
Experts from the CDC have arrived in Entebbe, Uganda to actively assist the Ugandan Ministry of Health, local health officials, and international organizations in disease response. At the present time, there are no other known cases.
On October 25, 2008, CDC received samples of pig tissues, sera and cell cultures from FADDL, the Foreign Animal Disease Diagnostic Laboratory on Plum Island, NY. The samples, originally collected from pig farms outside Manila, were initially tested at the Plum Island facility, which identified multiple swine pathogens, including Porcine Reproductive and Respiratory Syndrome (PRRS) virus and porcine circovirus type 2. Additional testing by molecular analysis also tentatively identified, for the first time in pigs, Ebola-Reston virus. Further testing of the samples at CDC’s Special Pathogens Branch and Infectious Disease Pathology Branch confirmed the presence of Ebola-Reston virus. Sequence analysis conducted at FADDL and CDC revealed that the virus is similar to the Ebola-Reston virus that infected macaques from the Philippines imported into the US for research in 1989, 1990 and 1996, and into Italy in 1992.
The clinical significance of Ebola-Reston in pigs is unknown, since many of the samples were obtained from pigs with dual PRRSV and Ebola-Reston virus infections. Epidemiologic investigations by Philippine authorities are continuing to look for evidence of human disease associated with infected pigs. Ebola-Reston virus is of unknown pathogenicity in humans. Recent studies of small numbers of Philippine slaughterhouse workers revealed antibodies to Ebola-Reston virus, with no clinical disease.
On November 26, 2007, CDC received blood samples from the Ugandan Ministry of Health, taken from 20 of the 49 patients involved in an outbreak of an unknown illness in Bundibugyo district in western Uganda. Patients reported fever, enteritis, and bleeding. Of the 49, 14 have died. Genetic sequencing of a small segment of viral RNA from samples indicated the presence of a previously unknown strain of Ebola virus. At the invitation of the Ugandan Ministry of Health, CDC, WHO, MSF and other collaborators deployed field investigators to the affected region; additionally, a laboratory was set up in Entebbe at the Uganda Virus Research Institute (UVRI). As the outbreak neared conclusion in January 2008, the total number of suspected cases was 149, with 37 deaths.
On August 28, 2007, CDC was notified of cases of an unidentified disease in a remote area of Kasai Occidental Province in the Democratic Republic of Congo (DRC). Clinical samples were sent to the CDC Special Pathogens Branch laboratory for testing, as well as to the Centre International de Recherches Médicales de Franceville (CIRMF) laboratory in Gabon. Results obtained by both Real Time PCR and viral antigen assay were positive for infection with Ebola virus. The presence of other diseases in the same area of the country contributing to the outbreak cannot be ruled out. At the invitation of the DRC Ministry of Health, CDC, WHO, MSF and other collaborators have deployed field investigators to the region. The onset of the latest laboratory-confirmed case was on September 29, 2007. On October 1, 2007, the total of suspected cases was 249 with 183 deaths.
According to the World Health Organization (WHO), 20 cases, including 5 deaths, from Ebola hemorrhagic fever (EHF) have been reported from Yambio County in southern Sudan. EHF has been laboratory confirmed by both the Centers for Disease Control and Prevention (CDC) and the Kenya Medical Research Institute. CDC has confirmed that the virus is the Ebola-Sudan strain (incubation period: 2-21 days), one of three previously recognized Ebola virus strains known to cause human disease.
For related information regarding travel, please see the CDC Travelers’ Health Web site.
For information regarding the recent cases of Ebola hemorrhagic fever syndrome in south Sudan, please refer to the World Health Organization's (WHO) Communicable Disease Surveillance and Response page.
For information regarding cases of Ebola hemorrhagic fever syndrome in The Republic of the Congo, please refer to the World Health Organization's (WHO) Communicable Disease Surveillance and Response page.
On May 6, 2002, the Gabonese Ministry of Health declared that the Ebola hemorrhagic fever outbreak in the Ogooué-Ivindo province had ended. CDC participated with the Gabonese and Congolese Ministries of Health, the World Health Organization (WHO), the International Center for Medical Research in Franceville, Gabon, and other partners in an international response to the outbreak in the Ogooué-Ivindo province of Gabon and in neighboring villages in the Republic of the Congo.
Ebola hemorrhagic fever is a severe, often fatal viral hemorrhagic disease. The virus can be transmitted by close contact with persons symptomatic with the disease. On the basis of extensive studies of previous outbreaks of Ebola hemorrhagic fever, general travelers in the area are unlikely to contract the disease. However, travelers are advised to take appropriate precautions to prevent infection. These precautions include avoiding direct contact with people who have serious disease and their bodily fluids.
For more information about the outbreak, please refer to the World Health Organization's Communicable Disease Surveillance and Response Page.
For more information on the disease, please refer to the Ebola Hemorrhagic Fever Fact Sheet[PDF - 252KB].
For basic recommendations on VHF infection control, please refer to the CDC and WHO manual: Infection Control for Viral Hemorrhagic Fevers In the African Health Care Setting [PDF - 2MB].
On February 27, 2001, Uganda was declared officially to be free of Ebola hemorrhagic fever, following a 42-day period, twice the maximum incubation period, during which no new cases had been reported.
Between October 2000 and February 2001, CDC participated with the World Health Organization (WHO), the Ugandan Ministry of Health,Medecins Sans Frontieres (MSF), and other partners in an international response to the outbreak.
For more information about the outbreak in Uganda or about viral hemorrhagic fevers in general, please refer to the following: