Frequently asked questions on Ebola virus disease vaccine

WHO:  1. Is there a vaccine for Ebola virus disease?

An experimental Ebola vaccine has shown to be highly protective against the Ebola virus. This product, called rVSV-ZEBOV. It was studied in several trials that involved more than 16,000 volunteers in Europe, Africa and the United States and has been judged safe for use in humans based on available results. In Guinea, the vaccine was tested in 7,500 adults in 2015 and found safe and protective against Ebola infection. This trial was conducted by WHO, with the Guinean Ministry of Health, Doctors Without Borders and the Norwegian Institute of Public Health, in collaboration with other international partners.
The Ebola vaccine, that has the technical name rVSVΔG-ZEBOV- GP, was developed by the Public Health Agency of Canada, licensed to NewLink Genetics, who in turn licensed it to Merck & Co. The vaccine works by replacing a gene from a harmless virus known as vesicular stomatitis virus (VSV) with a gene encoding an Ebola virus surface protein. The vaccine does not contain any live Ebola virus.

2. Is now the right time to use the candidate vaccine in DRC?

• The current outbreak is due to the Ebola Zaire. Strategic Advisory Group of Experts on Immunization (SAGE) recommended in 2017 that should an Ebola disease outbreak occur before the candidate vaccine is licensed, the rVSVΔG-ZEBOV- GP vaccine be promptly deployed under the Expanded Access framework, with informed consent and in compliance with Good Clinical Practice.
• Given the location and access challenges in the area, getting the vaccination teams to the affected area will be challenging but the Ministry of Health, MSF, WHO and partners are working together to address the logistics constraints.
• WHO has a small stockpile of rVSV-ZEBOV. Merck has provided this yet to be licensed vaccines and pledged to allow access to more.

3. Who authorized the use of this vaccine in DRC?

The protocol was reviewed and approved by the national regulatory authorities and the national ethics committee.

4. How will the candidate vaccine be administered and who will receive it?

Ring vaccination, is the recommended delivery strategy. This will be adapted to the social and geographic conditions of the outbreak areas and include people at risk including but not limited to: (i) contacts and contacts of contacts; (ii) local and international health-care and front-line workers in the affected areas and (iii) health-care and front-line workers in areas at risk of expansion of the outbreak. They constitute the “ring” for the vaccination. With their agreement and consent, the individuals in the ring will be considered for the vaccination. After receiving the candidate vaccine, they will be followed up for a set period of time.

5. Is participation in the ring vaccination voluntary?

Yes. Participation in this ‘expanded access’ or compassionate use of the Ebola vaccine is entirely free and voluntary. Each eligible person makes their own decision whether to participate or not and can withdraw at any time. Their rights will be respected. Disregard of whether the eligible person chooses to participate or not, it will not have an impact on their access to health services.

6. What will happen to people who will be included in the ring vaccination?

The team from the Ministry of Health, MSF and WHO will determine who is eligible to be vaccinated, depending on their level of risk and health condition. The following people will be considered for vaccination: (i) contacts and contacts of contacts, (ii) local and international health-care and front-line workers in the affected areas and (iii) health-care and front-line workers in areas at risk of expansion of the outbreak will receive an injection of the candidate vaccine in the arm. As a follow up, they will be visited in their homes to check their health six times – on days 3, 14, 21, 42, 63 and 84 after vaccination.
It is very important that the persons vaccinated continue to protect themselves from Ebola virus infection by not touching a patient's bodily fluids (blood, vomit, saliva, urine, feces), avoid being in direct physical contact with a patient's body (alive or dead), touching the sheets, clothes that may have been contaminated, practice hand hygiene and other preventive measures.

7. Can the vaccine cause side effects?

The vaccine can produce some side effects. People who are vaccinated may have a mild fever or cold like symptoms, malaise that can last 1-3 days. Among those vaccinated, one in five felt temporary swelling at the point of injection into the skin. Some people will have a mild and transient fever 1 to 2 weeks after the injection or some small blisters may appear. It is possible to have joint pain in the feet, hands or knees. Very rarely, vaccines can cause a serious allergic reaction immediately after the vaccine has been administered. This can cause breathing difficulties and weakness.

8. Can a person vaccinated be infected with Ebola by the vaccine?

The vaccine cannot cause the disease because there is no Ebola virus in the vaccine. The vaccine is manufactured according to international standards for vaccines. If a person receiving the vaccine has been infected with the Ebola virus before he/she is vaccinated, they could develop Ebola virus disease after they receive the vaccine. For those infected before the vaccination, the vaccine cannot provide protection. If they develop any symptom of illness, they should immediately contact the vaccination team.

Researchers Identify Chemical Compound That Inhibits Ebola Virus

Georgia: An organic chemical compound shows effective antiviral activity against Ebola virus and several other viruses, according to a study led by Georgia State University. The researchers found benzoquinoline inhibited the ability of Ebola virus to multiply and reproduce in cell culture. The findings are published in the journal Antiviral Research. Ebola virus, a member of the filovirus family, is an enveloped, single-stranded RNA virus that causes severe disease in humans. The largest outbreak on record for the filovirus family was caused by Ebola virus in West Africa between 2013 and 2016, resulting in more than 28,000 infections and more than 11,000 deaths.

Ebola survivors: life afterwards

INSERM: The long-term clinical and social sequelae following survival of Ebola infection are unknown. In November 2014, i.e. less than a year after the start of the Ebola epidemic in West Africa, Inserm, in partnership with the French National Institute for Sustainable Development (IRD) and the Department of Infectious Diseases at Donka University Hospital, Conakry in Guinea, organised medical follow-up of people who survived infection by the virus as part of a large research cohort. 802 individuals (adults and children) were included in the PostEbogui cohort from March 2015.
Results of follow-up show that on average one year after their initial period in hospital, 3 in 4 survivors still report health problems.

Ebola vaccine works in trial

Scimex: An experimental Ebola vaccine appears to work after it proved highly protective against the deadly virus in a major trial in Guinea. The vaccine, made by Merck, Sharpe & Dohme, is the first to prevent infection from one of the most lethal known pathogens, and the findings add weight to early trial results published last year. The vaccine, called rVSV-ZEBOV, was studied in a trial involving 11,841 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 the World Health Organization, together with Guinea’s Ministry of Health and other international partners.

Study finds people with Ebola may not always show symptoms

Stanford: A year after the Ebola epidemic in West Africa, researchers from the Stanford University School of Medicine and other institutions identified 14 individuals previously unknown to have had the disease in a Sierra Leone village that was an Ebola hot spot. These individuals had antibodies to the virus, suggesting they had been infected at one time. Yet 12 said they had had no symptoms during the time of active transmission in the village.

Has a new mutation in the Ebola virus made it deadlier?

Science: The sheer size of the Ebola epidemic that began in 2013 and engulfed West Africa is still a bit of a riddle for scientists. Previous Ebola outbreaks had never sickened more than 600 people. But the outbreak in Liberia, Sierra Leone, and Guinea infected more than 28,000 before it was finally brought under control. Part of the explanation was that the virus had suddenly surfaced in major cities, making it harder to stamp out than in the isolated rural locales where it had struck before. The countries’ poor public health infrastructure and other environmental factors played roles as well.
But two papers raise another intriguing possibility.

New test speeds up Ebola diagnosis

Scimex: A new test can accurately predict within minutes if an individual has Ebola Virus Disease (EVD), according to new research published in The Lancet. The study is the first to show that a point-of-care EVD test (ReEBOV Antigen Rapid Test; Corgenix) is faster than and as sensitive as a conventional laboratory-based molecular method used for clinical testing during the recent outbreak in Sierra Leone.

Pinpointing Ebola's recent outbreak origins

Scimex: A international team of researchers has managed to track down the origins of the Ebola virus, separately for Guinea, Sierra Leone and Liberia, and narrow down the timing at which the virus was transmitted across borders. They did this by analysing genetic differences in virus DNA from patient samples collected in Guinea during the outbreak and worked out, for example, that the Ebola virus from Guinea probably spilled over into Sierra Leone in April or early May 2014.

Scientists release Ebola sequencing data to global research community online

Cambridge: A team of scientists, part of the international effort to curb further spread of the Ebola virus in Sierra Leone, has released its first dataset of the virus’ genetic structure online. The dataset will allow the global scientific community to monitor the pathogen’s evolution in real-time and conduct research that can lead to more effective strategies against further outbreaks.

Experimental Ebola treatment boosts survival in mice

American Chemical Society: The number of new Ebola cases is tapering off, but the search for new treatments continues. Now, one research team has found potential drug candidates that successfully treated up to 90 percent of mice exposed to the Ebola virus. They report their findings in the journal ACS Infectious Diseases.

New study eases fears of airborne Ebola

University of Florida: At the peak of the Ebola epidemic last fall came a frightening new possibility: a mutation that could allow the disease to spread through the air. Now University of Florida researchers have dispelled this concern using data from current and past Ebola outbreaks. The team — led by associate professor Marco Salemi of UF’s Department of Pathology and Emerging Pathogens Institute, in collaboration with the Italian Institute of Health — revealed its findings in a study published today in Nature Scientific Reports.

Liberia is declared Ebola free

Nature: The World Health Organization announces the end of Ebola in Liberia, but the epidemic continues in nearby Sierra Leone and Guinea. Liberia is the first of the three main countries affected by Ebola to be free of the disease, marking the end of the 15-month-long epidemic in the country. But the epidemic continues in nearby Sierra Leone and Guinea, and the WHO is warning against complacency, highlighting the risk of further flare ups and geographical spread.

Do our genes determine whether we survive Ebola?

TheConversation: Despite killing a majority of people it infects, some patients survive the onslaught of Ebola virus. What gives them this resistance, ask Michael Katze, professor of microbiology, and colleagues from the University of Washington in a study published in the journal Science They used mice to answer this question because despite being infected with Ebola virus, they don’t show the symptoms seen in Ebola-infected humans. Mice tend to be a good animal model for scientists to understand human diseases, because they are easy to handle in labs and have been studied extensively. However, in the case of Ebola, it is their apparent resistance which may give us more useful answers.

Avengers 3: Ebola returns with a vengeance

St George's University: Health experts have warned that a greater flexibility must be brought to medical trials to combat diseases like Ebola to avoid facing another nightmare outbreak. The rapidity and spread of the Ebola outbreak and the urgency of a response led to many challenges not least of which was to advise those managing people on the ground of the best way to treat the illness and which treatments might be effective. The conventional design of medical trials may have been too time consuming, and demand recruitment of too many patients for what was a very urgent situation. The experts have urged a greater flexibility be used in future.

Ebola virus hasn’t become deadlier, yet

Manchester: Research from The University of Manchester using cutting edge computer analysis reveals that despite mutating, Ebola hasn’t evolved to become deadlier since the first outbreak 40 years ago. The surprising results demonstrate that whilst a high number of genetic changes have been recorded in the virus, it hasn’t changed at a functional level to become more or less virulent. The findings, published in the journal Virology, demonstrate that the much higher death toll during the current outbreak, with the figure at nearly 10,500, isn’t due to mutations/evolution making the virus more deadly or more virulent.

Vaccine against Ebola in sight - immunisation possible with just one injection

Vienna: A live vaccine based on the "Vesicular Stomatitis Virus" (VSV) has yielded highly promising results for the rapid development of an effective vaccine against the Ebola virus. This vaccine would only need to be injected once for long-lasting immunoprotection. These are the key findings of an international study coordinated by the World Health Organisation (WHO) in which the MedUni Vienna also played an important role. In this context, Markus Müller, Vice Rector for Research and Head of the University Department of Pharmacology, is acting within the VEBCON study consortium as head of the "Data Safety Monitoring Board" and is therefore jointly responsible for checking the vaccine's safety.

Ebola vaccine trial launching in Guinea

Scimex: Based on promising data from initial clinical trials in late 2014, WHO with the Health Ministry of Guinea, Médecins Sans Frontières (MSF), Epicentre and The Norwegian Institute of Public Health (NIPH), will launch a Phase III trial in Guinea on 7 March to test the VSV-EBOV vaccine for efficacy and effectiveness to prevent Ebola. The vaccine was developed by the Public Health Agency of Canada. A second vaccine will be tested in a sequential study, as supply becomes available.

Ebola in Liberia: Keeping communities safe from contaminated waste

WHO: Every day, every bed in an Ebola treatment unit creates approximately 300 litres of liquid waste. Managing this waste has been a challenge in the Ebola outbreak in Liberia. WHO is working with partners to ensure this waste is effectively decontaminated and no longer poses a threat to health.

Australian virus might be answer to effective Ebola vaccine

Queensland University. Australia: An experimental Ebola vaccine made using an Australian virus called Kunjin might help in the fight against the deadly Ebola virus, an international study led by The University of Queensland has found.

Could Ebola mutate faster than we can develop treatments?

UNSW. Australia: As the worst known epidemic of the Ebola virus continues in West Africa, scientists around the world are trying to develop treatments for those infected. But a process of viral mutation, known as “genetic drift”, could potentially compromise their efforts.