Ebola Outbreaks

Ebola Outbreaks 2024

Orthoebolaviruses are a group of four viruses that cause Ebola disease. The initial Zaire Ebolavirus disease (EBOV) case was confirmed in 1976 in a village near the Ebola River.  A study published on August 18, 2023, says the origins of Ebola remain enigmatic. Recent data suggest that some EBOV outbreaks may originate from human-to-human transmission of prior Ebola outbreak strains instead of spillover. According to the World Health Organization (WHO), Ebolavirus outbreaks frequently occur in Africa. As of 2024, more than 30 EBOV outbreaks have been reported. The WHO posted a Chronology of EBOV outbreaks.

Ebola Prevention and Control Guidelines 2024

In August 2024, the WHO published updated infection prevention and control research priorities in healthcare settings. Key recommendations are summarized in The BMJ. On December 18, 2023, Texas Biomed announced findings published in the Journal of Infectious Diseases (Sept. 2023) indicating that the Ebola virus creates and uses intercellular tunnels to move from cell to cell and evade treatments. "Our findings suggest that the virus can create its hiding place, hide, and then move to new cells and replicate," says Olena Shtanko, Ph.D., an Assistant Professor at Texas Biomed and senior author.

Ebola Disease in the United States

The U.S. CDC updated its Ebola Overbreak History on August 31, 2023. The CDC says eleven people were treated for EVD in the U.S. during Africa's 2014-2016 epidemic. On September 30, 2014, the CDC confirmed the first travel-associated case of Zaire EVD was diagnosed in the U.S. in a traveler from West Africa to Dallas, Texas. The patient (the index case) died on October 8, 2014. Two healthcare workers who cared for him tested positive for EVD, and both recovered. On October 23, 2014, a medical aid worker who had volunteered in Guinea was hospitalized in New York City, NY, and was diagnosed with EVD. The aid worker recovered, and seven others were cared for in West Africa. Six of these EVD patients recovered; one died, reported the CDC.

Zaire Ebolavirus Outbreaks

Africa endured Zaire Ebolavirus outbreaks between 2014, 2016, 2018, and 2022. Over 29,000 people were infected, and more than 11,000 died. The African countries most afflicted were Sierra Leone and Liberia. Since then, the DRC Ministry of Health has announced various outbreaks of EVD. During the 2018–2020 EVD outbreak in the eastern part of the DRC, among those offered vaccination, self-reported uptake of the Ebola vaccine was 99% (95% confidence interval (CI) [98.5–99.4]), As of August 2023, Original Research indicates that EVD surveillance systems in Liberia may fail to detect a new outbreak promptly. Specific improvements are required, and regular evaluations are recommended.

Sudan Ebolavirus Outbreak

On May 8, 2023, North Kivu, DRC, confirmed a positive case of Sudan Ebolavirus (SUDV). This revelation was made by the communicator of the provincial health division of Butembo, Dps-Butembo, Damulo Luhavo, during a press briefing. "Regarding Ebola virus disease surveillance, we received a sample that turned out to be positive from the Kyondo health zone and in the Butembo site. We have received four samples, and among the four, one is positive," said Damulo Luhavo.

The WHO declared the Sudan Ebolavirus outbreak in the Republic of Uganda on September 20, 2022. Since the outbreak declaration, it's the fifth overall for this kind of Ebola; the last outbreak was in 2012; there were 164 cases (142 confirmed and 22 probable), 55 confirmed deaths, and 87 recovered patients. Overall, the case-fatality ratio was 47%. There were 19 cases, with seven deaths occurring among healthcare workers. The last patient was released from care on November 30, 2022, when the 42-day countdown to end the outbreak began. 

The U.S. CDC reissued  Alert Level 2, Practice Enhanced Precautions notice on November 16, 2022, regarding the SUDV outbreak, as did Uganda's Government. In addition, on November 5, 2022, the U.S. Embassy in Kampala reported the U.S. had channeled more than $22.3 million through implementing partners to support the government of Uganda's led response to the current Ebola virus outbreak. Accordingly, the U.S. Embassy recommends deferring non-essential U.S. government employee travel to and through the Mubende and Kassanda districts. The CDC issued Health Alert Network Health Advisory CDCHAN-00477 on October 6, 2022, and CDCHAN-00480 on November 7, 2022. Since October 2022, all U.S.-bound passengers who have been in Uganda have been routed to designated airports for enhanced Ebola screening. The U.S. government conducted similar airport exit and entry screening for Zaire Ebolavirus in 2014.

The UKHSA issued a public health message on November 14, 2022, regarding the Sudan Ebolavirus outbreak in Uganda. All workers returning to the U.K. from areas affected by SUDV should be risk-assessed by the UKHSA. On November 1, 2022, the WHO advised against any travel and/or trade restrictions to Uganda based on available information for the current SUDV outbreak.

Virological.org's preliminary analysis of selected Sudan Ebola Virus isolates from the 2022 Uganda outbreak. Further investigation with more samples will be required to better understand the possible relevance of mutations to the current Ebola Sudan outbreak and future outbreaks in Uganda.

Marburg Virus Outbreaks

Marburg virus disease (MVD) outbreaks have been reported since 1967 in Germany and continue in 2023. 

Ebola Vaccines

Ebola vaccine information is posted at this Precision Vaccinations link.

Ebola Therapy

The U.S. Food and Drug Administration authorized Ebanga for intravenous injections on December 21, 2020.

Ebolavirus Diagnostic Tests

A novel patch-based ebolavirus diagnostic test was announced on August 18, 2023.

Ebolavirus Disease

The Ebolavirus family Filoviridae includes three genera: Cuevavirus, Marburgvirus, and Ebolavirus. Within the genus Ebolavirus, six species have been identified: Zaire, Bundibugyo, Sudan, Taï Forest, Reston, and Bombali. Ebola viruses (EBOV) assemble into filamentous virions whose shape and stability are determined by the matrix viral protein 40 (VP40). pH-driven structural remodeling of the VP40 matrix acts as a molecular switch coupling viral matrix uncoating to membrane fusion during EBOV entry. According to the WHO, EVD is transmitted to people from wild animals and spread through human-to-human transmission, with case fatality rates varying from 25% to 90%. Infection with the Ebola virus to symptom onset, including fever, fatigue, muscle pain, headache, and sore throat, can range from 2 to 21 days.