WATCH: The Fight Against Ebola
According to medical journal The Lancet, an Ebola vaccine trial in Guinea has proved 100 percent successful at preventing the spread of the virus in those vaccinated immediately after a close contact is diagnosed, suggesting an end to the epidemic could finally be in sight.
The VSV-EBOV vaccine, which combines the Ebola virus with a safer virus to train the immune system to beat Ebola, was given to the families and close contacts of Ebola sufferers in Guinea.
"The 'ring' vaccination method adopted for the vaccine trial is based on the smallpox eradication strategy," said John-Arne Røttingen, Director of the Division of Infectious Disease Control at the Norwegian Institute of Public Health. "The premise is that, by vaccinating all people who have come into contact with an infected person, you create a protective 'ring' and stop the virus from spreading further."
There was no spread of Ebola among the 2,014 people vaccinated immediately after someone close to them was diagnosed, despite their proximity to the patient. There were, however, 16 cases diagnosed among people who were vaccinated three weeks after an Ebola patient close to them had been identified. Dr Margaret Chan, Director-General of the World Health Organisation (WHO), called the trial "an extremely promising development".
So far, over 4,000 close contacts of nearly 100 Ebola patients have taken part in the trial. However, more conclusive proof that the vaccine can protect large groups is still needed, so the Guinean national regulatory authority and ethics review committee have approved continuation of the trial.
To date, more than 11,000 people have died of Ebola.