We spoke with Tarik Jasarevic of the World Health Organization (WHO) about the logistics of this vaccine. He informed us that the vaccine will be transported via a cold-chain and be stored in freezers at a temperature of roughly -5 degrees Celsius. The units will allow the vaccine to remain effective for two weeks.
There is no Ebola virus within the vaccine but a virus known as vesicular stomatitis virus (VSV) that has been genetically engineered to contain a protein from the Ebola virus species that is present in the outbreak. It is said to provoke an immune system response to protect those who have had the vaccine.
This vaccine will be given in a ring strategy, according to Jasarevic. This strategy involves administering the vaccine to those who have been exposed to the vaccine; contacts of contacts of contacts of Ebola virus disease patients, or anyone who has had contact with someone who had contact with an affected individual. The vaccine will not be administered on a country-wide scale but instead in this ring strategy – in a similar strategy to that which was used to eliminate small-pox.
Local and international health care workers in affected areas will also receive the vaccination. However, participation in the vaccinations is voluntary. If an individual chooses not to receive the vaccination they will still be allowed access to all health services. Pregnant women and children under six may not receive the vaccination.
MSD (known as Merck in North America) manufactured the vaccine and conducted a Phase III clinical trial that showed positive results in protecting against the Ebola virus.
Jasarevic told us that the vaccine is just one aspect of preventing and containing outbreaks. There are other steps that need to be taken that can be implemented to lower the risk of spreading the virus. Certain hygienic practices, like burials, are not able to be conducted due to cultural and religious practices of the area.
Roughly 33 people have died in the most recent outbreak in Eastern DR Congo, which came shortly after the outbreak in the northwest of the country was declared over. It is thus thought by Jasarevic that the same species of Ebola virus is present.
We recently reported that a first-in-human clinical trial is being conducted by the National Institute of Allergy and Infectious Diseases (NIAID).