Ebola Vaccine, Is It Safe?
Background: The Ebola virus kills its victims through shock and internal bleeding. Since Ebola is deadly, highly infectious and currently untreatable, a US company has developed and begun testing the first Ebola vaccine.
Study: The experimental Ebola vaccine is being tested for safety in over two dozen volunteers. Of these volunteers, 21 will get three injections of the Ebola vaccine over a two-month period and then be followed for one year. Six people will get placebo injections
Comment: This current study is designed only to evaluate the safety of the vaccine in humans and NOT whether it will protect humans from the Ebola virus. That will come later if the vaccine proves safe. In the meantime, it is frustrating that the new vaccine cannot be used in the Congo where a new Ebola outbreak is underway.
NIAID Ebola Vaccine Enters Human Trial
Nov. 18, 2003 -- The first human trial of a vaccine designed to prevent Ebola infection opened today. The vaccine does not contain any infectious material from the Ebola virus.
Just three years ago, a team of scientists described an experimental Ebola vaccine that fully protected monkeys from lethal infection by the virus. One component of that vaccine will now be assessed for safety in human volunteers. The trial vaccine, a type called a DNA vaccine, is similar to other investigational vaccines that hold promise for controlling such diseases as AIDS, influenza, malaria and hepatitis.
Anthony S. Fauci, M.D., Director of the National Institute of Allergy and Infectious Diseases (NIAID) said: "Our accelerated effort to understand and combat Ebola infection is part of the NIAID commitment to its biodefense mission. An effective Ebola vaccine not only would provide a life-saving advance in countries where the disease occurs naturally, it also would provide a medical tool to discourage the use of Ebola virus as an agent of bioterrorism."
Outbreaks of Ebola in Africa kill up to 90 percent of those infected. No effective treatment exists for this highly infectious disease, which causes extensive internal bleeding and rapid death. According to experts, vaccination is the best strategy for preventing or containing this deadly infection.
A gap of two decades separated the first Ebola epidemic of 1976 and the next, which arose in 1995. In recent years, for reasons unknown, outbreaks of Ebola are occurring with increasing frequency.
On November 17, 2003, the World Health Organization reported 11 cases of Ebola hemorrhagic fever in the Republic of the Congo. Dr. Nabel notes, "The current Ebola outbreak in the Congo provides a stark reminder of the need to rapidly develop vaccines against such perilous infections. A few years ago, we did not imagine that our vaccine would enter human trials so quickly, but the re-emergence of such viruses makes it all the more important to respond quickly. Individuals who volunteer for these vaccine trials can help us understand if our new vaccines ultimately will be effective."
Twenty-seven volunteers between the ages of 18 and 44 will participate in the study. Six people will receive a placebo injection and 21 will receive the investigational vaccine. In the new trial, volunteers will receive three injections over two months and will be followed for one year. Volunteers will not be exposed to Ebola virus.
The candidate vaccine is synthesized using modified, inactivated genes from Ebola virus. This gives the immune system information about viral structures so that it can mount a rapid defense should the real virus ever be encountered. There is no infectious material in the vaccine, and the virus was not present during any stage of the manufacturing process, notes Barney Graham, M.D., Ph.D., director of the clinical trials unit of the Vaccine Research Center at NIAID. "It is impossible for the vaccine to cause infection," he adds, "because it employs new technology known to safely stimulate broad immune responses."