Survivors with immunity may only need one dose

VACCINE side-effects are up to three times more common in people who have had coronavirus, figures show.

The Zoe app by King’s College London has logged information from more than 700,000 people who have had a vaccine, and the data show that those who have been infected are more likely to have side-effects. The difference was particularly pronounced among those who have had the Pfizer jab.

More severe side-effects are often a sign of better immunity, and emerging research suggests that one dose gives a similar level of protection as two in people who have had Covid. Scientists have started to question whether people with prior immunity from a natural infection need a second dose at all.

The Zoe data show that 12.2 per cent had side-effects after one Pfizer jab. For those with a previous infection the figure was 35.7 per cent. For the Oxford/ Astrazeneca jab, 31.9 per cent reported symptoms after their first dose, rising to 52.7 per cent with a previous infection. Most had muscle aches, headaches or felt groggy. Women were twice as likely as men to suffer side-effects from the Pfizer jab and 50 per cent more likely from the Astrazeneca one.

Ellie Barnes, professor of hepatology and immunology at Oxford University and one of the Oxford vaccine team, said: “There’s emerging data to show that when you’ve had a Covid infection your T-cells become activated and then over the weeks after that they become memory T-cells and kind of calm down. But they are then able to respond very rapidly to subsequent vaccination.”

Last month, researchers at Mount Sinai Hospital in New York found that people with prior infection had between 10 and 20 times more antibodies after their first vaccine than those without. The authors said that those with a previous infection would be unlikely to need a second dose, and supplies could be diverted elsewhere. The University of Maryland, in the US, also found a greater antibody response in healthcare workers who had previously been infected after vaccination.

Eleanor Riley, professor of immunology and infectious disease at the Edinburgh University, said: “Both papers suggest that people who have had a PCR confirmed Covid-19 infection may only require one dose of the vaccine... However, incorporating this into a mass vaccination programme may be logistically complex and it may be safer, overall, to ensure that everyone gets two doses.”