Since the beginning of the Ebola outbreak in West Africa, the world has been frantically looking for a way to contain and control it. Little did they know that the vaccine has been in progress for the last 10 years. A decade ago, scientists modified a chimpanzee cold virus to carry immunity to the Zaire strain of Ebola. Testing at the time confirmed that it was effective when used to treat monkeys but the benefits wore off over a short period of time, so it only provided temporary immunity to the Zaire strain of the Ebola Virus.
According to scientists, the progress of developing a vaccine in a lab were economical issues and not technical issues. Previous outbreaks were carefully controlled by mapping and tracing the virus, as well as quarantining the ill. Since most of the people who were coming down withe Ebola were unable to pay for services, the funding for research and developing a vaccine was limited to what individual countries could provide from their own scientific research funds.
The recent outbreak growing out of control turned the tables and caused countries to put forth more money to help control the outbreak before it stretched further than the rural portions of Africa. The advancement in research speed allowed for human trials of the vaccine a lot faster than initially planned.
Phase I Trials
Phase I trial contained 20 members. These members received the vaccine in September of 2014. Two members of this 20 person team experienced mild fevers but there were no serious illnesses. After about four weeks, all of the participants were producing Ebola antibodies. At least 1/2 of the members of this group received a dose that was ten times larger than the rest of the group. The group that received the larger dose resulted in the production of higher antibody concentrations.
Scientists noticed during animal trials that the success of the vaccine depended greatly on the production of CD8 T cells. These antibodies were necessary to produce complete immunity to contracting the Ebola Virus. Unfortunately, even though they have seen success in creating most antibodies, they have not seen continuous production of CD8 T cells. Out of the 20 volunteers, only 7 of the 10 people who received the higher dose, produced CD8 T cells.
Intentions of Phase I Trial
The intentions of the Phase I Ebola Vaccine trial was to determine whether the current serum would be effective in treating both the Zaire strain (that is currently ripping through West Africa) and the Sudan Ebola strain. Some of the participants only produced antibodies against one or the other strain, but most produced immune responses to both strains. There are two other vaccines in the first strain of Ebola testing that are specifically aimed at targeting the Zaire Ebola strain that is currently ravaging West Africa.
January Trial Plans
The plans for January trials are expected to target individuals that are at highest risk of contracting the virus. This is because the virus is still infecting an astronomical number of people in Sierra Leone and due to the high population that lives in close proximity to one another. It is projected by the CDC that the only way to successfully stop people from dying from this virus is to provide a vaccination to the people who are not already infected. Therefore, the most likely method of clinical trial will be in Africa and centered in Sierra Leone.