rVSV-ZEBOV has very promising results on a trial performed in 2015 with very promising results. The vaccine is not approved yet however it can be used during any epidemic occurring before approval after giving informed consent. INO-4212 is another promising vaccine under experimentation with the results of ongoing trials expected to be released by May 2018.
In 2015, A trial conducted in Guinea involving 11,841 subjects demonstrated the efficacy of rVSV-ZEBOV in preventing Ebola virus induced hemorrhagic fever in the 1st and 2nd degree contacts of patients infected with Ebola virus.[2]
The study utilized a“ring vaccination” design whereby each case contact (household contacts, workmates, visitors, etc) for 3 weeks prior to the onset of symptoms was followed and their network was mapped to form a "cluster". A total of 117 clusters were identified; each one consisted of approximately 80 individuals. Subjects (contacts of the infected individual) were randomized either to receive the vaccine immediately or 3 weeks after the start of the trial. The vaccine was given to those who are above 18 years of age.
After 10 days, none of the participants in the vaccinated group developed hemorrhagic fever. At the same time, 23 cases of Ebola virus infection were confirmed in the delayed vaccine group (who had not yet been immunized).cal
The vaccine is not fully approved yet, however, it can be available prior to approval during an outbreak through a “compassionate use" approval, meaning that it can be administered after signing an informed consent.
In light of the recent outbreak in the Democratic Republic of Congo[3], high hopes are held upon the "compassionate use" of rVSV-ZEBOV to limit the impact of the outbreak.