Ebola VaccineThe world is heaving a sigh of relief with the news of the discovery of a new vaccine against Ebola. The preliminary results of a WHO-led trial in Guinea, the results of which were published in The Lancet, show that “VSV-EBOV”, an experimental Ebola vaccine, is highly effective against the deadly virus.

The aim of the Guinea vaccination trial which began in affected communities in March 2015, was to assess the efficacy, effectiveness and safety of a single dose of VSV-EBOV using a ring vaccination strategy. The ring vaccination involves immunizing the immediate contacts of a person who falls ill with a virus so that a protective ring is created around them to stop transmission. Up to 4000 family members, neighbors, and co-workers of around 100 Ebola patients voluntarily participated in the trial.

Immediately after an Ebola case was detected, 48 rings were vaccinated. Another 42 clusters, which were considered a control group, were vaccinated three weeks later. the researchers compared how many people in each group tested positive for the virus 40 days after vaccination,. The results:

  • Of the 2,014 people who were vaccinated immediately, no one got Ebola.
  • Of the 2,380 individuals who got the shot three weeks later, 16 people fell ill.

The trial results prove that a single dose of the new vaccine is highly effective to protect against this viral infection and that it works in a larger population. That the vaccine can be distributed quickly is also a positive sign. However, experts say that there’s still a lot of work to do before the new vaccine is approved and deployed. The independent body of international experts that conducted the review has advised that the trial should continue.

The VSV-EBOV vaccine was developed by the Public Health Agency of Canada and licensed to Merck and NewLink.

Dr. Margaret Chan, WHO’s director-general said, “This is an extremely promising development. The credit goes to the Guinean government, the people living in the communities and our partners in this project. An effective vaccine will be another very important tool for both current and future Ebola outbreaks“.