A vaccine have been developed to fight our long term enemy Ebola, with a final test being a success on a series of human adults giving their bodies a partial immune response to the virus, which is a huge milestone in creating a cure!
What this vaccine (and all vaccines) do is allow the body to fight an invader that it would normally not recognize as being one, one the immune system can spot an invader it can protect itself. The vaccine will contain a small portion of the virus so the body can not only fight it but familiarize itself so should you ever get the same one it knows how to deal with it!
What’s the ebola virus?
“This is the first study to show comparable safety and immune response of an experimental Ebola vaccine in an African population,” says lead author Dr Julie Ledgerwood from the National Institutes of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health, USA. “This is particularly encouraging because those at greatest risk of Ebola live primarily in Africa, and diminished vaccine protection in African populations has been seen for other diseases.”
So how did they do it?
The scientists at NIAID constructed the DNA vaccines that allow the body to respond to the Ebola virus, the vaccine was created from Zaire and Sudan strains and the Marburg virus protein. These vaccines contain proteins on the outer layers of the virus, these proteins showed a high levels of reaction with immune systems of non-human mammals.
The trials where done in phases, firstly the Makerere University Walter Reed Program enrolled 108 healthy adults aged between 18 and 50 from Kampala, between November 2009 and April 2010.
Then each person was randomly allocated to receive an intramuscular injection of either the Ebola vaccine (30 volunteers), Marburg vaccine (30), both vaccines (30), or placebo (18) at the start of the study, and again 4 weeks and 8 weeks later the first injection.
The vaccines stimulated an immune response in the form of rallying antibodies and T-cells against the virus proteins. Four weeks after the third injection 57% of the volunteers now showed a direct response from their immune systems to the Ebola Zaire protein as did the other participants who received both the Ebola and Marburg vaccines.
When tested on Ugandan adults the same responses also occurred in them too, this was good news!
According to Dr Ledgerwood:
“These findings have already formed the basis of a more potent vaccine, delivered using a harmless chimpanzee cold virus, which is undergoing trials in the USA, UK, Mali, and Uganda in response to the ongoing Ebola virus outbreak.”
Dr Saranya Sridhar from the Jenner Institute at the University of Oxford in the UK says
“This study deserves to be the focal point around which the broader question of vaccine development, particularly for Africa, must be addressed. With the uncharitable benefit of hindsight in view of the evolving 2014 Ebola outbreak, we must ask ourselves whether a filovirus vaccine should have been in more advanced clinical development. The international response to the present Ebola outbreak is an exemplar of the speed and purpose with which clinical vaccine development can progress and has set the benchmark against which future vaccine development must be judged. This study is the first step on the aspirational road towards the deployment of filovirus vaccines in Africa and must serve to shake the metaphorical cobwebs that can stall our advance towards this destination.”
- Hannah Kibuuka, Nina M Berkowitz, Monica Millard, Mary E Enama, Allan Tindikahwa, Arthur B Sekiziyivu, Pamela Costner, Sandra Sitar, Deline Glover, Zonghui Hu, Gyan Joshi, Daphne Stanley, Meghan Kunchai, Leigh Anne Eller, Robert T Bailer, Richard A Koup, Gary J Nabel, John R Mascola, Nancy J Sullivan, Barney S Graham, Mario Roederer, Nelson L Michael, Merlin L Robb, Julie E Ledgerwood. Safety and immunogenicity of Ebola virus and Marburg virus glycoprotein DNA vaccines assessed separately and concomitantly in healthy Ugandan adults: a phase 1b, randomised, double-blind, placebo-controlled clinical trial. The Lancet, 2014; DOI: 10.1016/S0140-6736(14)62385-0