The rVSV-ZEBOV-GP Ebola vaccine has demonstrated high efficacy in the ring vaccination strategy in place in the Democratic Republic of the Congo (DRC), suggest preliminary findings.
DRC’s national research institute, the Institut National pour la Recherche Biomedicale and the World Health Organization conducted a preliminary analysis of the data being collected from the ring vaccination protocol to better understand whether or not the rVSV-ZEBOV-GP candidate vaccine is effective.
Between 1 August 2018 and 25 March 2019, 951 confirmed and probable cases of Ebola were reported. A total of 71 cases of Ebola occurred among the 93,965 people at risk vaccinated in 679 rings, whereas 880 cases occurred among at-risk individuals who were not vaccinated. Of the 71 Ebola cases occurring among vaccinated individuals, 15 cases had onset of symptoms 10 days or more post-vaccination and 57 cases had onset of symptoms 0-9 days post-vaccination. There were nine deaths among 56 cases with onset of symptoms 0-9 days after vaccination and no deaths among people where the illness onset occurred 10 days or more after they were vaccinated.
A more detailed analysis is currently being prepared.