According to Pascal Soriot, head of the Anglo-Swedish pharmaceutical company, the AstraZeneca vaccine could help ward off serious Covid-19 disease in older people for longer, noting that the UK currently has lower hospitalizations than large parts of Europe .
The vaccine, developed by AstraZeneca and Oxford University, has been widely used in the UK, where the number of people admitted to hospital has continued to decline, even as infections increase.
But it has been used much less in Europe, where an increase in infections and hospitalizations has put health services on a high alert. Austria, where 28.7 people per 100,000 are in hospital compared to the UK’s 12 per 100,000, imposed a full ban this week to help slow the spread of coronavirus.
In response to Soriot’s comments, scientists said too few studies measured the performance of the vaccines side by side to determine a specific correlation. Soriot also stressed there is no “evidence” of a link and further data is needed.
Talk on the BBC Today program, he said: “It’s really interesting when you look at the UK, there was a huge peak of infections, but not so many hospitalizations relative to Europe.”
Asked if it was related to the block’s failure to use the Oxford / AstraZeneca vaccine in older people, Soriot replied: “What I am saying is that T cells do matter and especially if it is related to the durability of the response, especially in older people, and this vaccine has been shown to stimulate T cells to a greater extent in older people. ”
T cells, which help the body “remember” previous infections and kill pathogens when they reappear, affect how long people are resistant to diseases they have previously contracted or been immunized against.
Asked about any connection to the use of the Oxford / AstraZeneca sting in older people, he said: “There is no evidence of anything – we do not know. But we need more data to analyze it and get the answer . ”
The UK has the Oxford / AstraZeneca stitch heavy at the start of his vaccination campaign, as it only began to immunize older and more vulnerable people. Many European countries have stopped using it, especially for younger people, over fears of a possible link with rare blood clots.
Lance Turtle, an expert on infectious diseases at the University of Liverpool, said trials and actual experience showed that the Oxford / AstraZeneca vaccine was “excellent” at stopping serious diseases and death, but no clinical trial showed its effectiveness. properly evaluated against other vaccines.
“That would be the only way to be sure one vaccine is really more effective than another,” Turtle said. Alternative samples manufactured by Pfizer and Moderna are made using a newer technology called messenger RNA.
Eleanor Riley, professor of immunology and infectious diseases at the University of Edinburgh, said trials indicated that the Oxford / AstraZeneca vaccine “initially causes higher levels of T cells than the mRNA vaccines”. The implication was that “it could provide longer-term protection against hospitalization and death,” she added.
Yet it was very difficult to make direct comparisons because the vaccines were rolled out at different times and in different groups of people with different underlying health conditions, she noted.
Matthew Snape, associate professor of pediatrics and vaccine at the University of Oxford, and lead investigator of the Com-COV trial, which compared antibodies and T-cell responses in those who received the Pfizer and Oxford / AstraZeneca stimuli, also injected a note of caution.
His study showed that while a single dose of the [Oxford/AstraZeneca] vaccine does cause a better T-cell response than the Pfizer mRNA vaccine, shortly after two doses the T-cell response was very similar ”. Researchers were now investigating what the reactions looked like up to six months after the second dose, he added.
The Oxford / AstraZeneca vaccine faces an uncertain future in the UK after being sidelined from the booster program, on which the country relies to avoid further restrictions.
Additional post by John Burn-Murdoch in London