The tests showed that it generates antibodies and so-called T cells that can fight the coronavirus. It remains to prove its effectiveness against the virus in the next phase
This Wednesday, Mexico and Argentina announced that they will produce and distribute the covid-19 vaccine developed by the University of Oxford in partnership with the AstraZeneca laboratory for Latin America.
This vaccine is one of the three most advanced of the 18 that are already being tested in humans in clinical trials, and last July 20 Oxford University made it known that it was proven safeand capable of eliciting an immune response in the testing phase.
Its efficacy against the virus remains to be demonstrated in the next phase of the trial.
The trials, involving 1,077 people, showed that the vaccine generates antibodies and so-called T cells that can fight the coronavirus.
The British laboratory’s findings are encouraging, but it must be emphasized that it is still too early to know if this is enough to guarantee protection.
Still need to prove whether the vaccine can keep people from getting sick or even lessen your symptoms.
“There is still a lot of work to do before it can be confirmed whether the vaccine will help manage the covid-19 pandemic, but these first results are promising,” said Sarah Gilbert, a researcher on the Oxford team.
How does it work?
The vaccine, called ChAdOx1 nCoV-19, It is made from a genetically modified virus that causes the common cold in chimpanzees.
It has been heavily modified so that it cannot cause infections in people and also to make it “look” more like the coronavirus.
To modify it, the researchers transferred genetic information from the “spike protein” of SARS-CoV-2, the crucial tool that the coronavirus uses to invade our cells, into the vaccine.
This means that the vaccine looks like the coronavirus, and this gives the immune system a chance to learn how to attack it.
What are antibodies and T cells?
The focus of studies on coronavirus studies has focused mainly on antibodies, but these are just a part of our immune defense.
Antibodies are small proteins made by the immune system that stick to the surface of viruses.
Neutralizing antibodies can deactivate the disease.
T cells, on the other hand, are a type of white blood cell that helps coordinate the immune system and can detect which cells in the body have been infected and destroy them.
Almost all effective vaccines induce both antibodies and T cells, also called T lymphocytes.
T cell levels peak 14 days after vaccination and antibody levels after 28 days.
The Oxford study is still too recent to understand how long this protection can last, according to the British medical journal. The Lancet.
The study showed that 90% of people developed neutralizing antibodies after one dose.
Only ten people received two doses, and all of them produced neutralizing antibodies.
“We don’t know the level required to achieve protection, but we can maximize the response with a second dose,” Andrew Pollard from the Oxford research group told the BBC.
Were there any side effects?
There were no dangerous reactions to the vaccine.
However the 70% of people in the trial she developed a fever or headache, symptoms the researchers say can be treated with paracetamol.
What are the next steps?
The main objective is to ensure that the vaccine is safe enough to supply to the population.
More than 10,000 people will participate in the next phase of the trials in the UK. 30,000 people in the US, 2,000 in South Africa and 5,000 in Brazil will also participate.
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What progress is being made with other vaccines?
The Oxford vaccine is not the first to reach this stage, US and Chinese laboratories have also published similar results.
The American company Moderna was the first to claim that its vaccine can produce neutralizing antibodies. That vaccine injects coronavirus RNA (its genetic code), which then begins to make viral proteins to trigger an immune response.
BioNtech and Pfizer companies have also had positive results using their RNA vaccine.
A technique similar to that of Oxford, developed in China, also looks promising.
However, all these attempts are practically at the absolute limit of scientific advancement and they have not been proven to work.
In total, there are 23 covid-19 vaccines in clinical trials around the world and another 140 in early-stage development.
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