Professor Andrew Easton, a virologu from the University of Warwick's School of Life Science, has called the results of a trail for an Ebola vaccine as "extremely positive".
"This is a major step forward and is the first evidence for an effective preventative treatment that has the promise of limiting the impact of any future outbreaks", said Professor Easton (http://www2.warwick.ac.uk/fac/sci/lifesci/people/aeaston/).
Professor Easton's comment in full:
The initial results of a vaccine trial for the prevention of Ebola virus disease and the results are extremely positive and the data show that the vaccine is highly effective at generating protection. The results have been achieved in a very short time due to the use of a ‘ring vaccination’ approach that is similar to the method that was used to successfully eliminate smallpox virus.
In this approach a ‘ring’ of individuals who have direct or secondary contact with an infected individual are identified and offered treatment. This is a social ring of contacts and is not limited by geography. In the study individuals were vaccinated either immediately or 21 days later to allow an assessment of the efficacy of the vaccine.
Importantly, the people who received the delayed vaccine were provided with all of the available guidance and assistance to reduce the risk of infection that would normally be given so the vaccine was compared against the current best practices available. After 21 days all participants were vaccinated to ensure that everyone had the opportunity to benefit from any beneficial effect of the vaccine.
The data show that no individuals receiving the vaccine developed Ebola virus disease when assessed 6 days or longer after the vaccination (anyone developing the disease earlier than this would be considered to have contracted the disease before vaccination). Modelling of the spread of infection in earlier studies have indicated that this type of successful intervention is likely to have a very significant effect on containing the spread of an outbreak. This is a major step forward and is the first evidence for an effective preventative treatment that has the promise of limiting the impact of any future outbreaks.
More work on the data from this study is required and additional questions remain to be addressed. These include how long the protective effect lasts in recipients of the vaccine and some aspects of safety, though there have been trials in healthy individuals that are very positive with relatively few adverse effects seen.
Some technical challenges remain such as the requirement to keep the vaccine stored at low temperature but that is not a major impediment and technologies are available to assist with that even in difficult to access parts of the world.