Two promising Ebola vaccines appear safe in trials conducted so far and will soon be tested on larger populations within three countries in West Africa most ravaged by the deadly virus. The announcement was made in Geneva by the World Health Organization (WHO) earlier today. This welcome news, along with a decline in new Ebola cases, has global health officials optimistic that the epidemic, which began last March, may finally get under control in the coming months.
There is no treatment or vaccine for the Ebola virus, but significant progress was made during this epidemic. There had been some testing during previous outbreaks, which were isolated geographically. But the number of countries grappling this past year with Ebola-infected patients, the large numbers in countries ill-equipped to respond, and the resulting significant worldwide response put efforts to find a successful treatment and/or a vaccine into overdrive.
Blood work to identify antibodies Ebola survivors developed fighting the disease lead to treatments used in recent months. In addition, potential vaccines were fast-tracked in several Western countries to eliminate the number of years and hurdles involved in developing a new drug.
Two potential vaccines underwent recent limited safety tests on humans. Britain’s GlaxoSmithKline made the first drug and the second was developed by Merck and manufactured by the Public Health Agency of Canada. The two drugs were tested on volunteers in several countries, including Switzerland, Gabon, Mali, Germany, Britain, Canada as well as the United States.
Both vaccines being tested exhibited “an acceptable safety profile” in initial testing, according to the WHO Assistant Director-General of Health Systems and Innovation Dr. Marie-Paule Kieny. As a result, the WHO, which is a United Nations health agency, has met with researchers, vaccine developers, regulators and others on plans for further trials.
Before the trials begin, vaccine manufacturers are trying to determine the appropriate dosage level. In preparation for the trials, research teams have been put in place as well as equipment, including refrigerators to store the Ebola vaccine tests.
Different approaches to testing will be taken in Liberia, Sierra Leone and Guinea, the three countries hardest hit in 2014. In Liberia, where nearly 3,500 have died, 9,000 people each will be given each vaccine and a third group will receive a control vaccine. In Sierra Leone, there are plans to test one vaccine on approximately 6,000 people. Guinea is using a “ring study” approach, in which the entire village or community surrounding each infected person is vaccinated. They expect to offer 4,500 people immediate vaccination and a similar population later.
Besides the two drugs currently being prepped for large scale testing, there are others at different stages of development in the US, Russia and China, according to Kieny. “At this time last year, I would say the cupboard (of options against Ebola) was empty … but now the cupboard is clearly filling up rapidly,” she said.
According to the WHO, there have been approximately 21,086 confirmed, probable or suspected cases of Ebola in the current outbreak. While the mortality rate in this epidemic has not been as high as previous outbreaks, the WHO puts the death toll at 8,289, but this number is believed to be under reported.
The highly contagious virus also had a severe impact on health-care workers. More than 800 of the people tending to victims caught the disease (including several Americans). Approximately 488 of those medical and aid workers died.
While health officials are excited that the two Ebola vaccines will soon be tested in the three disease ravaged countries, it would be too optimistic to hope that eventually the Ebola virus will be permanently eradicated. Polio, measles and other preventable illnesses still plague (pun intended) people around the world. But the fast track to a vaccine will undoubtedly prevent another large-scale outbreak.
By Dyanne Weiss