Story at a glance

  • The world’s first approved Ebola vaccine has arrived.
  • The vaccine has been shown to be 97.5 percent effective during outbreaks of the deadly virus.
  • The European Medicines Agency approved an Ebola vaccine on Nov. 11, and on Nov. 12 the World Health Organization prequalified the vaccine, paving the way for its use by other United Nations agencies and Gavi, the Vaccine Alliance.

The world now has its first approved vaccine against the deadly Ebola virus. On Nov. 11 the European Medicines Agency authorized the vaccine, called Ervebo, manufactured by U.S. drugmaker Merck. The next day, the World Health Organization (WHO) prequalified the vaccine, declaring it as a safe and effective preventative measure against Ebola. The vaccine is currently being deployed in the Democratic Republic of Congo (DRC) in “compassionate use” cases similar to a clinical trial, Nature reports

By prequalifying the vaccine, the WHO hopes to accelerate its dissemination, allowing United Nations agencies and Gavi, the Vaccine Alliance, to obtain and distribute the vaccine. Merck says that it will work with the Food and Drug Administration in the U.S. as well as agencies across Africa to secure broader approval.

“This is a vaccine with huge potential,” Seth Berkley, CEO of Gavi, said in a press release. “It has already been used to protect more than 250,000 people in the DRC and could well make major Ebola outbreaks a thing of the past.”

The active outbreak of Ebola in the DRC has claimed nearly 2,200 lives since August 2018 and infected more than 3,000. The current outbreak is second in scale only to the 2014 West African outbreak that killed 11,000 and sickened 28,000. 

The Ervebo vaccine is one of several vaccines against the virus, which causes internal bleeding, fever, vomiting and severe diarrhoea, but only Merck’s has been tested during an outbreak. Preliminary data suggest Ervebo is 97.5 percent effective, protecting over 90,000 people during recent outbreaks. 

More than 250,000 people in the DRC have received the vaccine under the compassionate use license, but its approval will pave the way for broader, less time consuming distribution. Ervebo protects against the Zaire strain of the virus, one of four known to infect humans, which is responsible for the vast majority of Ebola outbreaks since its discovery in 1976. 

David Heymann, an epidemiologist at the London School of Hygiene and Tropical Medicine, told Nature that the vaccine’s approval “makes a big difference,” but that it does not mark the end of research. “The message is that the research is not done...It’s really important to continue to study vaccines and develop those second and third-generation vaccines.” 

Additional research could determine the vaccine’s longevity, whether it can be extended via a booster or potentially extend it to other strains of Ebola.

Published on Nov 14, 2019