Scientists investigate mRNA vaccine technology to cure cancer and HIV
By Sola Ogundipe
There is no evidence that a third jab of the AstraZeneca vaccine is required despite new research suggesting that it has the potential to restore peak immunity.
According to research by the University of Oxford team that developed the vaccine, a booster at least six months after the second jab would bring immunity levels back to their peak – and significantly increases antibody and T-cell levels to the coronavirus, including variants
The director of the Oxford Vaccine Group, Professor Sir Andrew Pollard, said there was data from the new study to show that responses can be boosted by giving another dose of the vaccine.
But he said although antibody levels from the second dose wane over time there is currently no scientific case for giving a booster.
Available data show that two doses of the Astrazeneca vaccine prevent more than 90 percent of serious infections from the Delta variant.
“When we have high levels of protection in the UK population, and no evidence of that being lost, to give third doses now while other countries have zero doses is not acceptable. We have to make sure that other countries are protected,” said Pollard.
The Oxford team also tested the effect of leaving a gap of at least 45 weeks between the first and second dose.
“This is what we expect from vaccines. If you give more time for the immune response to mature you tend to see slightly better responses later on.”
Polard argued that having two doses is better than one dose, and so if there is a lot of transmission in the population and you have a lot of supply of vaccine, giving two doses seems to make sense.
“But if you have insufficient supply even having one dose will have a huge impact on reducing hospitalisations and deaths, so the priority would be getting the first dose into as many people as possible.”
Scientists regard mRNA vaccines as a breakthrough that will usher in a new era of medicine — a potential weapon against numerous other diseases.