With high rates of vaccination across the UK, the latest ONS data suggests that 1 in 2 people have COVID-19 antibodies.
The Office for National Statistics (ONS) has been examining trends in the rate of infection with COVID-19 across the UK and separately, the proportion of individuals who have detectable antibodies to the virus. The first report related to the period April to May 2020 at which time, only 7.4% of those sampled had COVID-19 antibodies. Although previous bulletins have considered the antibody prevalence over a 28-day period, because of the rapid rollout of the COVID-19 vaccination programme, the ONS is now able to create weekly estimates. In the latest bulletin, the ONS has also provided data on the percentage of people who have received a vaccination dose but which had been too low to model in earlier bulletins.
In England, an estimated 54.7% (95% CI 49.3% – 60.5%) of the population would have tested positive for antibodies if sampled in the week ending 14 March 2021. The estimate for Wales is slightly lower (50.5%) but similar to Northern Ireland (49.3%) although both are higher than the estimate for Scotland (42.6%). Nevertheless, a recognised limitation with these estimates is that prevalence of positive tests in the devolved nations is obtained from a smaller sample size and therefore subject to more uncertainty. As an example of how prevalence rates have quickly increased in England, the bulletin shows how only 3 months earlier in December 2020 only 13.5% of the population of England would have tested positive for COVID-19 antibodies. Interestingly, the bulletin reveals little variation in antibody prevalence across England, ranging from 60% in the North West (highest) to 50.3% (lowest) in the South East. Additionally, prevalence rates are very high in older people. For example, the prevalence is estimated to be 86% of those aged 80 years and older and 89% of those between the ages of 65 and 69 years. The ONS suggests that these higher figures most likely reflects a greater number of vaccinated individuals. In contrast, the estimated prevalence in those aged 16 to 64 years ranged from 40.9% to 57.6%.
Finally, the bulletin examines the relationship between the estimated number who have received at least one vaccination dose and those testing positive for antibodies. As an example, in England, there is a very close match between both estimates (54.7% antibodies vs 56.1% vaccinated) and a similar pattern is observed for each of the different English regions and the devolved nations.
Office for National Statistics. Coronavirus (COVID-19) infection survey, antibody and vaccination data for the UK: 30 March 2021.