The first direct test of a novel Ebola vaccine is due to be carried out by an international team, including scientists from France, Germany, the UK and the US, at a US university next month.
The vaccine, named CARV-E, was developed by French company Sanofi Pasteur and is being tested on healthy volunteers in the US.
However, the team has so far failed to develop the antibody needed for the vaccine to work.
It will then be tested on people in the UK who have been infected with the virus and their families.
It is the first vaccine to be tested directly on humans, in the United States.
Scientists have been waiting for this to happen for several months, with the first test taking place in the spring of this year.
There are currently about 1.7 million people living with the Ebola disease in West Africa.
There are also more than 1.1 million new cases and 1.2 million deaths in the region.
“The first clinical trial will show whether CARV can be used to effectively and safely prevent and treat Ebola in the future,” said Dr Andrew Weiden, an infectious diseases researcher at the US National Institutes of Health (NIH).
“There are many questions still to be answered, but we’re hopeful that this first test will provide important information to inform future research and development.”
What are the chances of developing the vaccine?
A study of the vaccine’s safety and effectiveness was recently published in the journal Lancet.
According to the study, the antibody should be able to bind to the Ebola protein, which is the main component of the virus, making it easier to be administered.
This should make it more effective at preventing the virus from re-entering the body.
And the researchers say that once the antibodies bind to Ebola, the vaccine should be effective in treating the virus in patients who do not have the virus themselves.
Why has the vaccine not been tested on humans yet?
The US team are currently using a small group of volunteers to develop their vaccine.
This has caused concern that some of the volunteers might have developed antibodies, which could cause serious side effects.
The vaccine has not been given to the US public yet.
Dr Weiden said that it would be important to monitor whether any of the people had developed antibodies.
“If we see that there are any adverse events that have been reported, we will immediately conduct an independent risk assessment,” he said.
“But it is not the role of the WHO to make the decisions about when a vaccine can be administered to a population.”
The vaccine is currently being tested in the lab, and there are some signs that it may be able be tested in humans.
Dr Ween said the trial would also help establish whether the vaccine could be used in a clinical setting.
“There have been several studies in which the Ebola vaccine has been tested in people, and we expect the vaccine will be tested again on humans soon,” he added.
“These studies will provide valuable information for future vaccine development.”
The trial is being led by Dr Martin Mazzocco, from the US Institute of Medicine, and Dr David Sinclair, from Imperial College London.
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