The Office for National Statistics (ONS) estimates that 89.8 per cent of adults in England would have tested positive for antibodies against Covid-19 if they’d had a blood test in the week beginning June 14. Testing positive for these antibodies suggests that a person has had Covid-19 or has been vaccinated against it. 

Figures for other parts of the UK are broadly the same. The ONS estimates that in Wales, 91.8 per cent of the adult population would have tested similarly. The figure for Northern Ireland was estimated at 87.2 per cent of the adult population, while in Scotland, the number was 84.7 per cent. “Across all four countries of the UK, there is a clear pattern between vaccination and testing positive for Covid-19 antibodies,” said the ONS. 

However, the detection of antibodies alone is not a precise measure of the level of immunity, it added.