Yes, there is an approved Ebola vaccine. The first one, called Ervebo, was approved by the FDA in December 2019 and is available for anyone 12 months of age and older. A second vaccine regimen was authorized in Europe in 2020. Both protect against the most common and deadliest strain of Ebola, and a global stockpile of hundreds of thousands of doses is maintained for outbreak response.
Two Approved Vaccines
Ervebo, made by Merck, is a single-dose vaccine. It was the first Ebola vaccine to receive full FDA approval and is the primary tool used during active outbreaks. In a landmark trial in Guinea during the 2014-2016 West Africa epidemic, Ervebo showed 100% efficacy: among people vaccinated immediately, zero cases of Ebola developed 10 or more days after vaccination, compared with 23 cases in unvaccinated groups.
The second option is a two-dose regimen from Johnson & Johnson, marketed as Zabdeno and Mvabea in Europe. You receive the first injection, then a second shot about 8 weeks later. Because the full course takes nearly two months, this regimen is better suited for preventive use in areas neighboring an outbreak rather than in the middle of one. The European Medicines Agency authorized it in July 2020 under “exceptional circumstances,” meaning complete clinical data couldn’t be gathered for ethical reasons (you can’t give a placebo during an Ebola outbreak and wait to see who dies).
How the Vaccines Work
Ervebo uses a clever workaround. Scientists took a harmless livestock virus called vesicular stomatitis virus and swapped in a piece of the Ebola virus, specifically the protein that studs the surface of the Ebola particle. When your immune system encounters this modified virus, it learns to recognize that surface protein and mounts a defense. If you’re later exposed to real Ebola, your body already knows how to fight it. Because the vaccine virus can replicate inside your body (unlike many vaccines), it produces a particularly strong immune response.
Who Can Get Vaccinated
Ervebo is approved for individuals 12 months of age and older. During outbreaks, the World Health Organization recommends a strategy called “ring vaccination,” where health workers vaccinate the contacts of confirmed Ebola patients and then the contacts of those contacts, forming a protective ring around each case. This approach proved highly effective in containing outbreaks in Guinea and later in the Democratic Republic of the Congo.
The two-dose Zabdeno/Mvabea regimen is typically reserved for health care workers, lab personnel, and communities in regions that border active outbreak zones, where there’s time to complete the full 56-day schedule before potential exposure.
Outside of outbreak settings, Ervebo is not routinely given in the United States or Europe. It is primarily stockpiled for rapid deployment. The WHO established a global stockpile target of 500,000 doses, and by October 2022 the reserve had reached roughly 437,000 doses available for emergency response.
Side Effects
Ervebo’s side effects are typical of vaccines that trigger a strong immune response. In clinical trials, 70% of adults experienced injection-site pain, 55% reported headaches, 39% had feverishness, and about a third felt muscle pain. Fatigue, joint pain, and chills were also common. Most of these symptoms were mild to moderate and resolved on their own.
Joint-related side effects deserve a mention because they were more notable than with most vaccines. Joint pain occurred in 7% to 40% of recipients across different trials, and a small percentage (up to 3%) had joint pain severe enough to prevent normal daily activities. Actual joint swelling was reported in under 5% of participants in most studies. For toddlers aged 12 months to 2 years, the most common reaction was feverishness, affecting 83% of children.
What the Vaccines Don’t Cover
Both approved vaccines protect only against the Zaire species of Ebola, which has caused the largest and deadliest outbreaks, including the 2014-2016 West Africa epidemic that killed more than 11,000 people. They do not protect against the Sudan species, which caused a 2022 outbreak in Uganda.
Several vaccine candidates targeting the Sudan strain are in early development. A chimpanzee adenovirus-based vaccine has completed initial safety testing in healthy adults in Uganda, and a few other candidates are in phase 1 trials. None are approved or available for emergency use yet, which means a Sudan Ebola outbreak today would still lack a vaccine-based response tool.