The percentage of people in private households that were likely to have tested positive for Covid-19antibodies in the week ending 28 March has levelled off in England, Wales and Scotland, says the Office for National Statistics (ONS).
In England, the rate of antibody positivity is an estimated 54.9 per cent, while the latest estimate for Wales is 49.1 per cent and for Scotland, it is 46.0 per cent.
The ONS said the rate has increased in Northern Ireland, up from 50.0 per cent in the previous week to 54.5 per cent in the week to 28 March.
The presence of Covid-19 antibodies suggests a person has been infected in the past or has received a vaccine.
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The latest figures show a fall in antibody positivity rates among older people, which was likely as the data does not yet show the impact of second doses of coronavirus vaccinations.
In England, the highest percentage of people testing positive for antibodies in the week ending 28 March was estimated to be those between the age of 65 and 69 (84.5 per cent), followed by the 70 to 74 age group (82.4 per cent, 75 to 79 (79.8 per cent) and over-80s (77.6 per cent).
The 16 to 24 age group accounted for the lowest percentage of antibody positivity.
The picture is similar in Wales and Scotland as the vaccine rollout continues. Over-45s were invited to book a vaccine appointment on Tuesday, after the government announced it had met its target to offer all over-50s a jab.
The ONS uses different age groups in Northern Ireland due to small sample sizes and estimates 78.0 per cent of people over 70 were likely to have tested positive for antibodies in the week to 28 March.
It said: “Across all four countries of the UK, there is a clear pattern between vaccination and testing positive for Covid-19 antibodies but the detection of antibodies alone is not a precise measure of the immunity protection given by vaccination.”
As of 12 April, more than 4 million Covid jabs have been administered across the UK. Of that figure, 32,250,481 were first doses and 7,857,396 were second doses.
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