Volunteers for the Ebola trial
A major trial on an Ebola vaccine has proven to be highly protective against the deadly virus, according to results published in the medical journal, The Lancet.
The experiment which was conducted in Guinea indicates that the vaccine – rVSV-ZEBOV – is the first to prevent infection from one of the most lethal known pathogens.
The vaccine was studied in a trial involving 1, 1841 people in Guinea during 2015. Among the 5,837 people who received the vaccine, no Ebola cases were recorded 10 days or more after vaccination.
In comparison, there were 23 cases 10 days or more after vaccination among those who did not receive the vaccine.
The trial was led by WHO, together with Guinea’s Ministry of Health, Medecins Sans Frontières and the Norwegian Institute of Public Health, in collaboration with other international partners.
“While these compelling results come too late for those who lost their lives during West Africa’s Ebola epidemic, they show that when the next Ebola outbreak hits, we will not be defenceless,” Dr Marie-Paule Kieny, WHO’s Assistant Director-General for Health Systems & Innovation and the study’s lead author, said.
The vaccine’s manufacturer, Merck, Sharpe & Dohme, this year received Breakthrough Therapy Designation from the United States Food and Drug Administration and PRIME status from the European Medicines Agency, enabling faster regulatory review of the vaccine once it is submitted.
Since Ebola virus was first identified in 1976, sporadic outbreaks have been reported in Africa. But, the 2013–2016 West African Ebola outbreak which resulted in more than 11, 300 deaths highlighted the need for a vaccine.
The trial took place in the coastal region of Basse-Guinée, the area of Guinea still experiencing new Ebola cases when the trial started in 2015. The trial used an innovative design, a so-called ‘ring vaccination’ approach – the same method used to eradicate small pox.
In addition to showing high efficacy among those vaccinated, the trial also shows that unvaccinated people in the rings were indirectly protected from Ebola virus through the ring vaccination approach (so called ‘herd immunity’).
“Ebola left a devastating legacy in our country. We are proud that we have been able to contribute to developing a vaccine that will prevent other nations from enduring what we endured,” Dr Keïta Sakoba, Coordinator of the Ebola Response and Director of the National Agency for Health Security in Guinea, said.
 BY Jamila Akweley Okertchiri