Ebola Vaccine Proves To Be Very Effective
A vaccine to fight Ebola is showing very promising success:
In a development that could change the way the deadly Ebola disease is fought, researchers have announced promising results of a new vaccine’s trial in Guinea, one of several countries affected by a historic outbreak in West Africa.
“The estimated vaccine efficacy was 100 percent,” a team of researchers say.
The trial was called Ebola ça Suffit — French for “Ebola that’s enough.” Funded by the World Health Organization and other groups, it started in April and ended on July 20, relying on participants who consented to be part of the trial. The more than 20 researchers who took part published their findings in The Lancet medical journal on Friday.
“The current data basically tells us that the vaccine works to protect people against Ebola,” says Dr. Bertrand Draguez, medical director of Médecins Sans Frontières,which took part in the research along with WHO and authorities in Guinea.
Draguez and other experts are heartened by the new results — but they also warn that as testing expands, the effectiveness rate of the vaccine will likely fall below 100 percent. The trial used the “ring vaccination” method, in which all suspected contacts receive treatment. No placebos were administered.
“Even if the sample size is quite small and more research and analysis is needed,” Draguez says, “the enormity of the public health emergency should lead us to continue using this vaccine right now to protect those who might get exposed to the disease: contacts of infected patients and front-line workers.”
The trial vaccine, formally called rVSV-ZEBOV but more commonly known as VSV-EBOV, was supplied by the pharmaceutical firm Merck Sharp & Dohme. The drug was initially developed by Canada’s Public Health Agency and was tested as early as 2011.
To conduct the Guinea trial, researchers used newly confirmed Ebola cases to identify clusters of people with whom the patients had contact. On a random basis, those clusters then received the vaccine either immediately or after a 21-day delay.
“In the immediate vaccination group, there were no cases of Ebola virus disease with symptom onset at least 10 days after randomization,” the researchers say, “whereas in the delayed vaccination group there were 16 cases of Ebola virus disease from seven clusters, showing a vaccine efficacy of 100 percent.”
Researchers say that for both groups — those who got the vaccine immediately and those who received it after a delay — no new Ebola cases were diagnosed starting at six days after vaccination.
While Ebola largely disappeared from American headlines after the last patients that were diagnosed were treated and released late last year, it still remains a problem in the three western Africa nations that were source of last year’s outbreak. Fortunately, the number of new cases being reported is far, far below what it was even a years when the epidemic was just beginning. However, that incident reminded us that the virus remains in the environment in Africa and could easily reappear. Given how it ended up passing through international borders, and more important infecting the health care workers that were in country to treat people, a development like this that could stop another outbreak in its is very positive. Hopefully, the trials will continue to give us good news and we’ll be ready the next time the virus returns.