In response to the ongoing outbreak of Ebola in Equateur Province, Democratic Republic of the Congo, WHO with The Government of the Democratic Republic of Congo and partners, is preparing to vaccinate high risk populations against Ebola virus disease (EVD) in affected health zones.
The vaccines are donated by MSD (known as Merck in USA), while Gavi, the Vaccine Alliance is contributing $1 million towards operational costs. The Ministry of Health with WHO, Medecins Sans Frontieres (MSF), UNICEF and other key partners are implementing a ring vaccination with the yet to be licensed rVSV-ZEBOV Ebola vaccine, whereby the contacts of confirmed cases and the contacts of contacts are offered vaccination. Frontline healthcare workers and other persons with potential exposure to EVD – including but not limited to laboratory workers, surveillance teams and people responsible for safe and dignified burials – will also receive the vaccine.
A ring vaccination strategy relies on tracing all the contacts and contacts of contacts of a recently confirmed case as soon as possible. Teams on the ground have stepped up the active search and follow up of all contacts. More than 600 have been identified to date. The vaccine consists of a harmless livestock virus genetically engineered to display Ebola surface proteins. An experimental vaccine can be given as part of a trial under what are known as compassionate use regulations.
WHO has sent special vaccine carriers, which can keep their contents in sub-zero temperatures for up to a week and has set up freezers to store the vaccines. The Ministry of Health, WHO, UNICEF and partners are engaging communities to inform people about Ebola, including the vaccine.
The vaccine was shown to be highly protective against Ebola in a major trial in 2015 in Guinea. Among the 5,837 people who received the vaccine, no Ebola cases were recorded nine days or more after vaccination. While the vaccine is awaiting review by relevant regulatory authorities, WHO’s Strategic Advisory Group of Experts on Immunization (SAGE) has recommended the use of the rVSV-ZEBOV Ebola vaccine under an expanded access/compassionate use protocol during Ebola outbreaks linked to the Zaire strain such as the one ongoing in the DRC.