Ebola Vaccines

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Last reviewed
November 20, 2021

Ebola Vaccines

Ebola Zaire vaccines are U.S. FDA and European Medicines Agency Approved and administered to protect people from contracting the Ebola virus disease (EVD) in various countries. 

Ebola vaccines include replication-deficient adenovirus vectors, replication-competent vesicular stomatitis, human parainfluenza vectors, and virus-like nanoparticle preparations.

The Ebola virus is a zoonotic pathogen that causes severe hemorrhagic fever in humans, says the U.S. CDC. The CDC publishes a timeline of the previous Ebola outbreaks.

Zaire Ebolavirus Vaccines

Ervebo (rVSVΔG-ZEBOV-GP) is a recombinant, replication-competent Ebola vaccine.

Ebola Vaccine Regimen Zabdeno and Mvabea is a prime-boost vaccination approach and contains an antigen from the Sudan species.

Ad5-EBOV is an adenovirus type 5 vector-based Ebola virus disease vaccine.

Note: Ebanga (mAb114) is a human monoclonal antibody for treating Zaire Ebolavirus infections in adults and children. Ebanga is a human IgG1 MAb targeted to the Zaire ebolavirus glycoprotein, available in a lyophilized form. Furthermore, the EMA reviewers of Ebola vaccinates are found at this link.

Ebola Sudan Vaccine Candidates

IAVI’s rVSV Sudan ebolavirus vaccine candidate (rVSVΔG-SUDV-GP) is conducting a phase II clinical trial. There are no licensed vaccines against Sudan ebolavirus.

The University of Oxford ChAdOx1 biEBOV vaccine is targeted against the Zaire and Sudan species of Ebola and is conducting a phase 1 study.

INOVA's INO-4201 is composed of a precisely designed DNA plasmid that is injected intradermally followed by electroporation using a proprietary smart device, which delivers the DNA plasmid directly into cells in the body and is intended to produce a well-tolerated immune response; currently conducting phase 1b clinical research.

Ebola Vaccine News

November 16, 2021 - INOVIO that several volunteers have been dosed with its DNA-based, intradermal Ebola vaccine candidate, INO-4201, as part of a randomized, placebo-controlled, Phase 1b clinical trial, that will assess whether INO-4201 can be used as a booster in healthy volunteers previously vaccinated with rVSV-ZEBOV (Ervebo).

November 11, 2021 - The University of Oxford began recruiting for a Phase I trial that will assess the immune response and safety of the new vaccine against the Zaire and Sudan species of Ebola. Participants will receive one dose of the ChAdOx1 biEBOV vaccine. Following vaccination, participants will be monitored through several visits over a six-month period, with results expected in the second quarter of 2022. The vaccine is based on the ChAdOx1 virus, a weakened version of a common cold virus (adenovirus) that has been genetically modified so that it is impossible for it to replicate in humans. Volunteers interested in enrolling in the study can do so online.

November 7, 2021 - The WHO Africa reported the overall case fatality rate (CFR) is 81.8% (9/11) and 75.0% (6/8) among confirmed cases in the recent Ebola outbreak in the DRC. Children under the age of five years account for 50% (4/8) of the Ebola cases. A total of 485 persons have been vaccinated against EVD from the inception of the vaccination activities.

November 4, 2021 - The U.S. CDC published a Level Three Travel Advisory for the recent Ebola outbreak in the Beni Health Zone of the Democratic Republic of the Congo.

November 3, 2021 - The U.S. CDC vaccine advisory committee reviewed previous recommendation preexposure vaccination with Ervebo for adults aged ≥18 years in the U.S. population who are at highest risk for potential occupational exposure to Ebola virus species Zaire ebolavirus because they are: responding to an outbreak of Ebola Virus Disease (EVD), or work as health care personnel at federally designated Ebola treatment centers in the U.S., or work as laboratorians or other staff at biosafety level 4 facilities in the U.S.

November 2, 2021 - The WHO reported additional cases and deaths confirmed in the Ebola virus disease outbreak in the Democratic Republic of the Congo with two new health areas affected. A total of 394 people (67 primary care providers including nine high-risk contacts, nine contacts of contacts, and 49 probable contacts) have been vaccinated including 182 contacts of contacts, 125 probable contacts, and 87 high-risk contacts.

October 29, 2021 - A Research Article - Safety and immunogenicity of 2-dose heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola vaccination in healthy and HIV-infected adults: A randomized, placebo-controlled Phase II clinical trial in Africa - was published by the journal PLOS Medicine. Conclusion - The Ad26.ZEBOV and MVA-BN-Filo combo vaccination were well tolerated and immunogenic in healthy and HIV-infected African adults. Increasing the interval between vaccinations from 28 to 56 days improved the magnitude of humoral immune responses. Antibody levels persisted to at least 1 year, and an Ad26.ZEBOV booster vaccination demonstrated the presence of vaccination-induced immune memory. These data supported the approval by the European Union for prophylaxis against EBOV disease in adults and children ≥1 year of age.

October 27, 2021 - IAVI announced an award of up to US$126 million from the Biomedical Advanced Research and Development Authority to develop two recombinant vesicular stomatitis virus (rVSV)-vectored filovirus vaccine candidates. This award supports preclinical activities and includes options for clinical development up to and inclusive of a Phase II clinical trial of IAVI’s rVSV Sudan ebolavirus vaccine candidate (rVSVΔG-SUDV-GP). Optional work that would continue the development of IAVI’s Marburg virus vaccine candidate (rVSVΔG-MARV-GP) that is currently supported by the Defense Threat Reduction Agency of the U.S. Department of Defense could be funded at a later date.

October 21, 2021 - The Sabin Vaccine Institute announced that the US Biomedical Advanced Research and Development Authority had exercised the third contract option, valued at $34.5 million, under the 2019 contract to advance the development of vaccines against Ebola Sudan and Marburg viruses through Phase 2 clinical trials.  

October 20, 2021 - The WHO African Region reported 5 Ebola cases, and over 27,000 travelers have been screened in the DRC. Furthermore, over 116 people have been vaccinated.

October 17, 2021 - Africa News reported Ebola vaccinations started in Beni, DRC, after at least two people died due to the virus in October 2021. The WHO African Region Tweeted DRC Situation Report (17/10/21) 5 confirmed cases, three deaths, 369 contacts identified, and 308 contacts monitored.

October 13, 2021 - Democratic Republic of the Congo (DRC) health officials confirmed an Ebola vaccination campaign had launched in the North Kivu province where one confirmed Ebola case, plus three related suspected deaths, were recently reported. About 1,000 doses of the rVSV-ZEBOV Ebola vaccine and other medical supplies were delivered from the capital Kinshasa to Goma city in North Kivu. The DRC has more than 12,000 vaccine doses in Kinshasa that can be deployed if necessary.

October 10, 2021 - The WHO reported additional Ebola cases related to the recent DRC case of a 3-year-old boy. A cluster of three deaths (two children and their father) who were neighbors of the case. These three patients died on 14, 19, and 29 September 2021 after developing symptoms consistent with Ebola. However, none were tested for the virus. As of October 9th, a total of 148 contacts have been identified and are under follow-up by the local response team.

October 8, 2021 - A case of Ebola has been confirmed in the eastern Democratic Republic of the Congo, five months after the end of the most recent Ebola outbreak there. The child died on October 6th. It was not immediately known if the Ebola case was related to the 2018-20 outbreak that killed more than 2,200 people in eastern Congo or the flare-up that killed six people in 2021.

September 13, 2021 - A new study based in Sierra Leone concluded the Ebola vaccine regimen from Janssen - J&J. It was found well tolerated with no safety concerns in children aged 1–17 years and induced robust humoral immune responses, suggesting the suitability of this regimen for Ebola virus disease prevention in children.

August 31, 2021 - The government of Cote d'Ivoire has informed the WHO that a second laboratory has tested samples from a patient suspected of having Ebola and has found no evidence of the virus. Around a dozen WHO experts were mobilized to support the country's efforts, and 5,000 Ebola vaccine doses which WHO had helped Guinea procure were sent from Guinea to Cote d'Ivoire.

August 23, 2021 - The WHO African region reported Ebola booster dose vaccinations in Sierra Leone following administration of the prime dose of the Johnson & Johnson Ebola vaccine in May 2021. Frontline health workers, practitioners of traditional medicines or traditional healers, and commercial motorbike riders who received the first dose are now given their second jab to maximize their protection against the disease. 

August 17, 2021 - The WHO confirmed Cote d'Ivoire deployed 2,000 vaccine doses from Merck and around 3,000 vaccine doses manufactured by Johnson & Johnson - Janssen.

August 14, 2021 - The WHO Africa reported the Ministry of Health of Cote d'Ivoire today confirmed the country's first case of Ebola since 1994. This came after the Institut Pasteur in Cote d'Ivoire confirmed the Ebola Virus Disease in samples collected from a patient hospitalized in Abidjan's commercial capital after arriving from Guinea.

August 9, 2021 - The WHO confirmed 'Marburg virus disease (MVD) is a highly virulent, epidemic-prone disease associated with high case fatality rates (CFR 24-90%). In the early course of the disease, the clinical diagnosis of MVD is difficult to distinguish from other tropical febrile illnesses because of the similarities in the clinical symptoms. Differential diagnoses to be excluded include Ebola virus disease, as well as malaria, typhoid fever, leptospirosis, rickettsial infection, and plague.'

July 6, 2021 - New York-based Mount Sinai researchers uncovered the complex cellular mechanisms of the Ebola virus, which could help explain its severe toll on humans and identify potential pathways to treatment and prevention. The study team reported how a protein of the Ebola virus, VP24, interacts with the double-layered membrane of the cell nucleus, leading to significant damage to cells and virus replication and the propagation of disease. 

June 15, 2021 - The Southwest National Primate Research Center at Texas Biomedical Research Institute (Texas Biomed) has been awarded more than $37 million from the U.S. National Institutes of Health to continue operations into 2026. The P51 grant, given by the NIH Office of Research Infrastructure Programs, provides essential funding to house and care for nearly 2,500 non-human primates that are part of life-science research programs at Texas Biomed and partners around the globe.

June 4, 2021 - Johnson & Johnson welcomed a new recommendation by the Strategic Advisory Group of Experts on Immunization for the WHO that supports the use of the Johnson & Johnson Ebola vaccine regimen both during outbreaks for individuals at some risk of Ebola exposure and preventively, in the absence of an outbreak, for national and international first responders in neighboring areas or countries where an outbreak might spread.

June 4, 2021 - J&J confirmed about 235,000 people had received at least the first dose of the Janssen two-dose Ebola vaccine regimen.

April 10, 2021 - The government of Sierra Leone and the WHO announced Johnson & Johnson had donated about 4,500 Zabdeno and Mvabea Ebola vaccines to Sierra Leone to help prevent any Ebola outbreak. The last Ebola outbreak in Sierra Leone was in 2016.

April 6, 2021 - Denmark-based Bavarian Nordic A/S announced the Company had received a new supply order from Janssen Pharmaceutica NV valued at approximately USD 28 million. Under the contract, Bavarian Nordic will manufacture and deliver bulk drug substance of MVA-BN® Filo vaccine, licensed to Janssen as part of its Ebola vaccine regimen, Zabdeno® (Ad26.ZEBOV) and Mvabea® (MVA-BN Filo). The manufacturing of the bulk drug substance will begin in May 2021, and delivery is expected to occur in the second half of 2021.

March 25, 2021 - Ohio Gov. Mike DeWine revealed health officials are monitoring 44 people who have returned from areas of Africa with active outbreaks of Ebola.

March 25, 2021 - Oregon public health officials announced they are monitoring four people who recently visited the West African countries of Guinea and the Democratic Republic of the Congo. Regions in each of these countries are currently experiencing outbreaks of Ebola virus disease. The Oregon Health Authority and local public health departments have been in contact with these individuals, considered "persons under monitoring" since they arrived in the state earlier in March 2021.

March 23, 2021 - The WHO African Region Tweeted Guinea Ebola outbreak Situation Report (22/03/21) 18 cases, nine deaths, 78 contacts, 82% monitored. And 3,905 people have been vaccinated.

March 13, 2021 - After a request from the Guinean authorities, Russia is considering supplying a domestic vaccine against the Ebola virus to the African country, reported TASS.

March 13, 2021 - The ECDC reported the results from genome sequencing confirmed that the first cases were infected with the Zaire ebolavirus species and suggested that the ongoing outbreak is genetically linked to the 10th EVD outbreak that occurred between 2018 and 2020 in the North Kivu and Ituri provinces in the DRC. The source of infection of the index case is currently unknown, and investigations are ongoing.

March 12, 2021 - The U.S. CDC issued a Warning - Level 3, Avoid Nonessential Travel, for the DRC. If your job requires possible exposure to Ebola, get vaccinated. On January 8, 2021, the CDC's Advisory Committee on Immunization Practices recommended pre-exposure prophylaxis vaccination with rVSVΔG-ZEBOV-GP (Ervebo™) for adults ≥ 18 years of age U.S. population at highest risk for potential occupational exposure to Ebola virus species Zaire ebolavirus.

March 5, 2021 - The Lancet published a study' infectious disease outbreaks expose the shortcomings in health-care systems. The Ebola outbreak pointed to gaps in training and resources as not all U.S. hospitals were ready and equipped to manage a patient with suspected or confirmed Ebola. During the 2014–16 Ebola outbreak in West Africa, academic (medical and public health) institutions worldwide contributed faculty and staff to respond.

February 25, 2021 - The U.S. CDC's vaccine advisory committee discussed Ebola vaccine status and options.

February 10, 2021 - In this study published by PLOS, researchers observed that EBOV RNA persistence in semen was a frequent phenomenon, with high population rates over time. This finding will inform forthcoming updated recommendations on risk reduction strategies relating to sexual transmission of EBOV. In addition, these findings support the implementation of a semen testing program as part of epidemic preparedness and response. Further, the results will enable planning of the magnitude of testing and targeted counseling needs over time.

February 3, 2021 - The Democratic Republic of the Congo (DRC) Crisis Response Plan 2021. The International Organization for Migration (IOM), in collaboration with its partners and other crisis response actors, seeks to provide urgently needed multisectoral humanitarian assistance, stabilization, and recovery support to conflict-affected populations in the DRC. IOM will also support the government in responding to the COVID-19 pandemic and post-Ebola stabilization efforts and strengthening preparedness for future public health hazards. Considering the many requests for accurate displacement data in the DRC, IOM also aims to expand the scope of its Displacement Tracking Matrix interventions to cover the entire country, including monitoring population mobility to inform the outbreak preparedness and response.

January 29, 2021 - Ebola Situation Report #37: Democratic Republic of the Congo (DRC) - The Ebola outbreak in the northeast of the DRC, the country's 10th and second-largest in world history, claimed the lives of 2,287 of the 3,324 patients affected. The 11th outbreak in Équateur Province affected 13 of the province's 18 health zones, with 130 confirmed cases and 55 deaths. The introduction of an Ebola vaccine in the DRC in 2018 enabled the country to mitigate the last three outbreaks impact. About 372,800 people have been vaccinated against Ebola (including 39,859 in Équateur province).

January 27, 2021 - Study: Ebola virus antibody decay–stimulation in a high proportion of survivors. The highest antibody reactivity was observed around 200 days after an individual had recovered. The model suggests that EBOV antibody reactivity declines over 0.5–2 years after recovery. In a high proportion of healthy survivors, antibody responses undergo rapid restimulation. Vigilant follow-up of survivors and possible elective de novo antigenic stimulation by vaccine immunization should be considered to prevent EBOV viral recrudescence in recovering individuals and mitigate the potential risk of reseeding an outbreak.

January 12, 2021 - A global emergency stockpile of 500,000 doses of Ebola vaccine, funded by Gavi, will be available to all countries for outbreak response following a procurement process concluded by UNICEF with a vaccine manufacturer. Gavi-eligible low- and lower-middle-income countries will access the stockpile free of charge. In addition, they will receive support for operational costs to conduct outbreak response immunization activities. The reserve will include licensed doses of the Ebola vaccine manufactured by MSD, known as Merck, inside the United States of America and Canada, which has received approval from the European Medicines Agency and the U.S. Food and Drug Administration, in addition to prequalification from WHO. The first deliveries of doses into the stockpile are funded through a $20 million contribution from the United States Agency for International Development, committed in 2017 and dedicated to supporting a supply of licensed Ebola vaccines to help tackle future disease outbreaks.

January 12, 2021 - Today, four leading international health and humanitarian organizations announced a global Ebola vaccine stockpile to ensure outbreak response. With the support of humanitarian organizations, the supply will allow countries to contain future Ebola epidemics by providing timely access to vaccines for populations at risk during outbreaks. The injectable single-dose Ebola vaccine Ervebo (rVSV∆G-ZEBOV-GP, live) is manufactured by Merck and developed with financial support from the U.S. government. The European Medicines Agency licensed the Ervebo vaccine in November 2019. The vaccine is now prequalified by WHO and approved by the U.S. Food and Drug Administration and eight African countries.

January 8, 2021 - The U.S. CDC published Use of Ebola Vaccine: Recommendations of the Advisory Committee on Immunization Practices, United States, 2020. The ACIP recommends preexposure vaccination with Ervebo for adults aged ≥18 years in the U.S. population who are at highest risk for potential occupational exposure to Ebola virus species Zaire ebolavirus because they are responding to an outbreak of EVD, work as health care personnel at federally designated Ebola treatment centers in the United States, or work as laboratorians or other staff at biosafety level 4 facilities in the United States.

International Coordinating Group on Vaccine Provision

Leading international health and humanitarian organizations announced a global Ebola vaccine stockpile to ensure outbreak response. The ICG was created as an additional tool to help control Ebola outbreaks. Ebola outbreaks are relatively rare and unpredictable in nature, and due to limited vaccine quantities, the current Ervebo vaccine is reserved for outbreak response. An initial 6,890 doses will be made available on a priority basis for outbreak response starting January 12, 2021. To request access to ICG stocks, national or international health authorities should submit an application form to the ICG Secretariat or an ICG member agency present in the country.

Ebola Antivirals

There are two antiviral treatments authorized to treat EVD, says the CDC. On October 14, 2020, the U.S. Food and Drug Administration (FDA) approved an antibody cocktail from Regeneron that's been shown to reduce Ebola-related mortality rates. The treatment, known as REGN-EB3, is a mixture of (3) monoclonal antibodies (atoltivimab, maftivimab, and odesivimab-ebgn) and is marketed under the brand name Inmazeb. Inmazeb is indicated to treat infection caused by Zaire ebolavirus in adult and pediatric patients, including neonates born to a mother who is RT-PCR positive for Zaire ebolavirus infection.

On December 22, 2020, Ridgeback Biotherapeutics L.P. confirmed that the U.S. FDA approved Ebanga to treat Ebola. Ebanga is now approved to treat infections caused by Zaire ebolavirus in adult and pediatric patients.

Ebola Vaccine History

Ebola virus is a zoonotic pathogen that causes severe hemorrhagic fever in humans, known as Ebola virus disease (EVD). There are four species of the Ebola virus that have been known to cause disease in humans. Zaire ebolavirus (EBOV) is the most lethal species, with case fatality rates of 70–90% if left untreated.  Ebola virus, also known as Zaire ebolavirus, Sudan ebolavirus, and Bundibugyo ebolavirus, can cause severe hemorrhagic fever, leading to high case fatality rates (30–90%) in humans, says the US CDC. On August 11, 2014, the WHO convened a meeting and concluded an "ethical imperative" to develop experimental Ebola vaccines. West Africa is experiencing the largest, most severe, most complex Ebola virus disease outbreak in history.

RESTV is the only ebolavirus that has not shown any symptoms in humans, thus far only seen in monkeys from the Philippines (being held in quarantine facilities in the United States and Italy) and on a pig farm in the Philippines.

On December 19, 2019, the U.S. Food and Drug Administration announced the approval of Ervebo to prevent EVD caused by Zaire ebolavirus in individuals 18 years of age and older. This report, published by the U.S. CDC on January 8, 2021, summarizes the Advisory Committee on Immunization Practices (ACIP) recommendations for using the rVSVΔG-ZEBOV-GP Ebola vaccine (Ervebo) in the USA.

On July 1, 2020, the European Medicines Agency granted Johnson & Johnson Janssen's Zabdeno and Mvabea Ebola vaccine therapy, a prime-boost vaccination approach for preventing infectious diseases. Janssen's Ebola vaccine regimen is specifically designed to induce long-term immunity against the Ebola virus in adults and children aged one year and above.

CanSino Biologics's Ad5-EBOV Ebola vaccine received approval in China in October 2017. Ad5-EBOV is an adenovirus type 5 vector-based Ebola virus disease vaccine that protects against Ebola by relying on the recombinant replication-defective human adenovirus type-5 vector immune response. In addition, Ad5-EBOV is manufactured as a lyophilized powder, highly stable, and does not require storage at ultra-low temperatures. This feature renders it viable for use in resource-limited tropical areas.

The WHO published the revised Ebola Vaccine FAQ on January 11, 2020.

Ebola Outbreaks in Africa

The 12th Ebola virus disease outbreak was declared in February 2021. Then on June 19, 2021, the Republic of Guinea declared the EVD outbreak over after four months. The country's 12th Ebola outbreak occurred in and around Butembo and ended with 11 confirmed cases, one probable case, and six deaths.

However, on August 14, 2021, the Republic of Côte d'Ivoire government has declared a case of an Ebola virus disease in the capital city of Abidjan. An early analysis of the Ebola virus from the Ivory Coast, recent Ebola case, suggests ties to the virus that circulated in West Africa's massive outbreak from 2014 to 2016, reported the World Health Organization regional office for Africa on August 17, 2021.

The Democratic Republic of the Congo's 10th Ebola outbreak lasted for nearly two years was the second largest in the world. There were 3,481 cases, 2,299 deaths, and 1,162 survivors.

Note:  Content Sources for this page include the World Health Organization, the US Centers for Disease Control and Prevention, clinicaltrials.gov, and the Precision Vaccinations news network.  Dr. Robert Carlson has reviewed this information.